oral history of lloyd thorndyke; 2011-07-12

Oral History of Lloyd M. Thorndyke

Interviewed by:

Gardner Hendrie

Edited by: Dag Spicer

Recorded: July 12, 2011 Arizona

CHM Reference number: X6277.2012

© 2011 Computer History Museum

Oral History Lloyd M. Thorndyke

CHM Ref: X6277.2012 © 2011 Computer History Museum of 93

Hendrie: Well, we have with us today Lloyd Thorndyke, who's graciously agreed to do another oral

history for the Computer History Museum. Thank you very much, Lloyd for giving us the opportunity to talk

to you some more about your many-faceted career at Control Data, and other companies. I think I'd like

to just clear up one thing that came up on your previous interview. You had mentioned that a designer at

DEC, Digital Equipment Corporation, had actually grown up in the same town, and went to the same high

school as you. Could you just elaborate a little bit on that, and who it was?

Thorndyke: He was an older person than I, probably about four years, I would imagine, and the name is

Ben Gurley, and I just heard that he had started in the computer business very early, had been one of the

really early pioneers, from the time that he got out of MIT, and his dad was a district judge, and then the

family moved, as apparently he was promoted one way or another, as I remember it, and so I was just

questioning, I knew that he was expired, he was killed some way or another. I was just mentioning it. The

first time I understood the background of it.

Hendrie: Okay. How far away did he live? He was in the same—

Thorndyke: Oh, a couple of blocks. I walked by their house to school.

Hendrie: Okay, very good. Now when you graduated, I know you went into the—you were drafted into the

navy.

Thorndyke: I was.

Hendrie: Yes, but it was 1945, is that correct? You graduated June of '45?

Thorndyke: The reason I was drafted, into the navy, was radar. MIT started the Radiation Lab as a result

of the fact that the British could not produce the magnetron, and they finally decided—they sent it over on

a cruiser and the MIT people were set up to start to design the magnetron for production. Well you can

see how good a job they did, because it's in every radar set. So over time, they figured out how to make

it, and the magnetron could make very good microwaves. And up to that time, the Germans, and nor

anyone else could. Now supposedly, during the war, you're never supposed to fly that thing within so

many miles of the coast, but I guess some guy got lost and landed in occupied territory, so the Germans

got the design, I think, eventually. But nevertheless, they found that the navy, in testing her people to find

ones to service a radar set, I think less than half a percent of the navy enlisted people could pass a

technology test.



Hendrie: So they needed electronic technicians, because there were radars on every ship.

Thorndyke: Right, and all the people that serviced their equipment, just took the box off, and put a new

box in. They couldn't understand what's in the box, or they’d just take [out] vacuum tubes and swap them,

put a new vacuum tube in, and if that doesn't do it, you're done. And the problems are that for radar, you

had to have some fundamental understanding. There had to be impedance matching, between the

magnetron and the waveguides and the antenna and all that sort of stuff. And if you didn't do that, it didn't

have any range, so you had a device—

Hendrie: Yeah, you had tremendous losses.

Thorndyke: Right. So they said, the solution is, let's go out to high schools and test the high school

students, to see if we can find the high school students who can do this. I took the test in the spring of

'44, and there were 100 kids in our school, and two of us passed the test, and then I volunteered in July of

'44, for service, and I was told to go back and finish high school, and then they'd take me. And they said,

we'll take you through the draft.

Hendrie: Okay, now how come you were able to pass the test? Was it courses you took, or things that

you tried building on your own, or how come you understood enough to pass the test?

Thorndyke: Well my dad was an entrepreneur inventor, if you wish, that type, and we had access to a lot

of tools and technology. He used to set us down every evening at dinner, and ask us—what's the area of

the Atlantic Ocean? What's the area of Minnesota? How many counties in Minnesota? Eighty-four. Area,

32 million square miles. Pacific, 64, and all that type of area, and so you start picking it up, and we'd read

books, like, Edison's books, and some of those books. So basically it was picking up because of what he

knew and said, and he was a farm kid that went to farm school, but back there in the '20s, he decided to

take a windmill and put a generator with a propeller on it, and generate electricity for the house. And that

was well before Lee-J [ph?] that finally came in and later on. But he ended up having a wind generator

that put out enough voltage, so he had a light in the house, as long as the wind blew. And then later on—

Hendrie: So he did it all, he just figured it out on his own.

Thorndyke: Figured it out, right, and he had the early crystal sets that no one could figure out how to

make a crystal set work.

Hendrie: Okay, so he had early radios and—



Thorndyke: And he had a very high mechanical intellect. So anyway, we passed the test, and then—

Hendrie: Was he a farmer, though? I mean, how did he make his living?

Thorndyke: Right, we—he was a farmer, I was born on a—

Hendrie: And you grew up on a farm.

Thorndyke: Grew up on a farm, and I was born on the farm, and then the Depression came along and

forced him off the farm, because it couldn't support two families. He farmed with his dad, and so it forced

us to move into town in '32, which was probably fortunate, because I was then entered into a good high

school, or grade school.

Hendrie: Yes. What did he do?

Thorndyke: He got a job as a registrar of deeds, not a political job, just a government type job. And he

registered deeds for the counties, and all the registration and that sort of area. And I don't think he ever

made more than about 2,500 dollars a year.

Hendrie: Yeah. But it was a good, steady job, and a secure job, because it wasn't a political job.

Thorndyke: He was a hell of a poker player.

Hendrie: Really?

Thorndyke: Oh God. He used to shear the guys. They had poker and he'd come home with some fair

amount of winnings, and it was not unlimited, it was a friendly area, it's a dime and a quarter and three

raise, and you're done. But he was very good in figuring odds and mathematical stuff in his head. So he

was very good. Right now, he would have been looked at as a very high intelligence in his—everything

was in powers of ten. And so he learned early on of the powers of ten, and he was also—in school, he

ended up having a lot of Latin, so he was very good with words.

Hendrie: Ah, so he was very good with languages.



Thorndyke: Yeah, so anyway, they took me then, in June, I registered, July pre-induction, and August, in.

August, I was in it on the 11th, five days after the first A-bomb.

Hendrie: Oh wow. Okay, so you just hit the very end.

Thorndyke: Yeah, and I had a brother that was two and a half years older, that was a B-17 pilot, that was

killed in March of '45.

Hendrie: In Europe, or in Japan?

Thorndyke: In Europe. So the folks were kind of—in fact, my mother was suggesting that, as the sole

surviving son, I could stay out. Well, gosh—oh, one of the things about the ________ Test, after you pass

and come in, you come in as a Seaman First Class. Now you go to boot camp as a recruit seaman, then

you get Seaman Second Class and Seaman First Class is equivalent of a Corporal.

Hendrie: Yeah, okay.

Thorndyke: So I went to boot camp at 66 bucks a month.

Hendrie: Very good.

Thorndyke: And of course there were a lot of people, we were only one group, they called us RTs, Radar

Technicians, and everybody else was getting 50, and of course we were always ridiculed and everything

else. But that's a separate story about that. But anyway, back in about, probably about '38 to '40, REA,

Rural Electrification came in. And in about the '42 to '43, timeframe, I would guess, it came in where we

were. So farms needed to be wired. Except anybody with any knowledge, had already been drafted, so I

started wiring farms. Now a problem is that I didn't understand the code.

Hendrie: But you understood electricity.

Thorndyke: I could put sockets in and switches and everything else. The three way switch was a little

more difficult. So anyway, yeah, I'm sitting on ladders and stringing stuff, and you know, I still, of course,

do electrical stuff today, and the areas that you work are hot. People say, you're working hot, as long as

you don't touch anything. And my son needed a circuit breaker changed in his master panel, at 440 volts,

and I said, "Yeah, I can change that." And so I pulled the circuit breaker out, but you know, everybody

was all spooked. And I said, "No, what we do is we get a big board here, and put a rug on top of it, and tie



a rope around me, and you stand over there about 10, 12 feet, and if I get across something, then you

just yank me out." And I said, "I won't touch anything, no metal tools or anything," and so I said, "You've

got to touch two places in order to get hurt."

Hendrie: Yes, exactly, the electricity has to go through you.

Thorndyke: Go through, and go back to return.

Hendrie: Yeah, exactly.

Thorndyke: As long as you don't touch anything, or fall over or anything—

Hendrie: Or stand in water, or do something really stupid like that.

Thorndyke: So I pulled it out, put the new circuit breaker in, and they thought, Jesus—and then after I got

out of service, as a digression, we needed to put 440 volts into a heater element to dry a component. I

went down and pulled the circuit breakers, and come back up and started wiring, and got across to the

240 volts, or 440 volts with a screwdriver, and it melted about four inches off the screwdriver, and

afterwards, I found out that someone had wired around the circuits, because they were heating—and

overheating the circuit through contact resistance, and melted the fuse with heat. So all the circuits were

bypassed in an old building.

Hendrie: Oh my goodness.

Thorndyke: So I wired it hot. I didn't get shocked, I didn't get killed, but, only by the grace of God. He

was looking after me I guess.

Hendrie: All right, so you go into radar as a radar tech, but you end up at the Office of Naval Research?

Why was that?

Thorndyke: Well we started junior college, and the navy came through, and they said, oh, by the way, 40

percent—or 75 percent of you people are going to get wiped out. And then you're going to go out in

mothballed ships. And so that kind of bothered us, and—

Hendrie: By being wiped out—you mean flunked out.



Thorndyke: Yeah. So 25 percent are going to be promoted, 75 percent are going to be sent out there on

mothballed ships.

Hendrie: Oh wonderful.

Thorndyke: The thing that bothered me, is that us kids from the Midwest, and there were probably about

10 or 12, or maybe 20 out of the 240 in the company were at a disadvantage. The rest of them, almost all

of them were kids from New York City that had gone to CCNY for two years.

Hendrie: Oh my goodness, okay.

Thorndyke: And of course they could pass the test very easily. And they were very clannish, the New

York City kids, and so us yokels from the country were deemed subhuman from their standpoint. They

came in with big K&E slide rules on their waists, and I had never seen a slide rule. So they had to teach

slide rules.

Hendrie: So you had no idea what that was.

Thorndyke: They taught slide rules as if you didn't know it, and so yeah, the New Yorkers finished there

fast, but by God, yokels got it done also. So we got done, and I made that cut, and then we went to Great

Lakes for the second school. Well, we spent time in Navy Pier in Chicago, in the winter. Colder than Billy

Hell.

Hendrie: Yeah, okay.

Thorndyke: You've got the wind coming off the lake, you know, and the warehouse was the barracks.

Hendrie: I see, okay.

Thorndyke: So anyway, then we went to Great Lakes, and then you could go to three different places.

You could go to Corpus Christi, you could go to Treasure Island, or the Naval Research Lab. And

everybody wanted to go to Treasure Island, because, after all, that's in San Francisco. But I didn't know

that, because I'd never been there, and as such, it probably sounded sexy to me, to be in the Naval

Research Lab. And so I and only one other person chose the Naval Research Lab. Everybody wanted to

go to Corpus Christie, and be an Airedale, we called them. And so we went out to Great Lakes, and then

from Great Lakes, after I completed the course, I went to Washington, D.C. in the spring. 75 percent of us



washed out, and only 25 percent advanced, and I luckily advanced. I don't know if the fact that most of

them wanted to go to Corpus Christie, and I didn't, made any difference.

Hendrie: Yeah, they—yeah. They weren't going to wash out the people who want to go to the Naval

Research Lab.

Thorndyke: So when we get to the Naval Research Lab, we find that the technology weapons of the

Germans come through the la, though in different buildings, and so we walk over and look at a jet plane.

And say, well what is this thing?

Hendrie: Oh really? And so they're taking the German technology and trying to understand it and figure

out what it is.

Thorndyke: And incidentally, I've never verified it, but comments were made that the Germans had

developed iron oxide tape, on acetate backing. The US went down the road of wire recorders very early,

if you remember, and we didn't develop the oxide tape for quite a while..

But in '43, they developed these oxide tapes, audio tapes. They would record on the tape, the

instructions from the Admiral, and what they would do is they would then speed up the recording, call up

the submarine and get everything ready, and all of a sudden, just a brip—it's sent to the submarine. And

the recorder in the sub had a high-speed tape in it also, and then they'd decode it, by slowing it down to

one and a half inches a second, to get the message. We never ended up breaking the code.

Hendrie: Because it wasn't a code, in a sense.

Thorndyke: Yeah, we didn't have the capability of capturing the transmission. The wire recorder wouldn't

do it, even though we had a few wire recorders. Well, supposedly the rumors say, and I know nothing

more than what was stated, that one of the people that went over to Germany to review their technology,

was a Mr. Poniatoff. I think was his name. And so he latched onto that technology, brought it back, and

they named a company after him. It's A.M. Poniatoff Excellence, AMPEX.

Hendrie: A.M. Poniatoff Excellence, AMPEX, wow.

Thorndyke: A-M-P-E-X. And that was—and I don't know if that's true or not, but that was a comment

made, that he was over evaluating it, and latched onto the acetate tape with the iron oxide coating.



Hendrie: Thought this was a really good idea, and—

Thorndyke: And really, developed a lot of technology. But I learned there, that when you're looking at a

new technology, you've got to make sure you can explain it in very simple terms. Because later on, as we

started talking about all our technology, of flying heads and integrated circuits, you're talking mostly to

people that don't really understand it, so you can't turn around and start using the engineering shorthand

approaches or verbiage approaches, you've got to make it simple enough they can understand it. You're

not trying to make them designers, just enough that, obviously, you're trying to sell them

Hendrie: You have to use plain English instead or all these—yes.

Thorndyke: Yeah, you're trying to sell them. And so, as such, I used that naval experience, trying to

explain [to] people, that, well here's what we really do. But anyway, then toward the end of—about May of

'46, the navy started letting reservists out. Now since I was in the reserve, and not a regular navy

volunteer, I was—well let me back up a second. In the class at Naval Research Lab, was a series of

senior petty officers that were radio men in that area, that wanted to become career people. The only

career path was radar. Brand new, no one's in it, reservists were all going home. They had a heck of a

problem with, how do you service it, because all of the people in the radar program were generally

reservists, and they went home to college.

Hendrie: Right, and these radio—

Thorndyke: All they did was replace vacuum tubes.

Hendrie: That's how they serviced radios, yes, they didn't need to understand it.

Thorndyke: And so the problem existed that, with radar, you have to get in and replace components and

circuits and everything, because you can't have an extra radar set on a ship, because they didn't have

enough radar sets being produced. So therefore, you had the components and you were expected to go

in and figure out what component burned out, and replace it.

Hendrie: Okay, so other components, besides tubes, tended to burn out in radar.—

Thorndyke: Capacitors and that like, and as such, why, you were expected to—and of course, part of the

program—part of the program was to build a radio. So they gave you the parts, you build a radio, and

tune it, and figure out how to do it. Well, I think, to some extent, they kind of looked at us small time kind



of farm kids and stuff, as being very dexterous in building things, as against the New York City kids that

probably had very little. We had—

Hendrie: They had never built anything in their life.

Thorndyke: And later on in life, I found that, if I could recruit small town kids, farm kids, ranch kids, they

understood responsibility. The city kids, generally, tended to be, well, get someone else to do it, rather

than just jump in, they said, well, don't volunteer for anything, and so they tended to have a different—

they were street smart, but not work smarts. Because there's not a lot of jobs in town, one way or another,

but I, through my life, I always tried to hire ranch kids, farm kids, small town kids. I could recruit to the

Rocky Mountains, if I recruit a kid from the west coast, it's like he had an invisible rubber band on him,

and after about a year and a half, ping, he's back to the west coast. I could recruit to about Ohio State,

and the east coast, I had a very good female engineer that came in and interviewed, and first thing she

wanted to know, where's your metropolitan museum of art. And I said, well, back here, you know, we end

up communicating with nature. We go canoeing, we go hiking, camping, and she lasted two weeks before

she had to go back to New York City. I can go south all the way to Texas. Anyway, that's an afterthought.

Hendrie: Yeah, let's get back to Naval Research Lab, and your—

Thorndyke: So I started—a guy said, what did he talk about today? So after dinner, we sat down, about

six of us, and I said, well, we went through this and this and this today. Pretty soon, I had probably 15 or

20 guys, they brought in a blackboard, and we would talk for maybe three hours, trying to tell how the

vacuum tube work, you've got all these curves in a vacuum tube, with voltage and screen voltage, and

what's all that mean? And so, as such, I started teaching. And the advantage was, in hindsight.

Hendrie: Yeah, you weren't really teaching, but effectively you were teaching, though you didn't have a

job to teach.

Thorndyke: Yeah, I knew—I could understand what they were talking about and everything, so anyway,

all the other reservists were discharged in April and May, and here I went all the way into August, and

then toward the end, why they come in, and says, well we've got to put radar people out on Enewetak

Atoll for the A-bomb tests, and if you would sign over for two years, we'll guarantee a promotion, so one

year at chief. What the hell, you go to third, second, first and chief, all in one year, but because of the

brother had been killed, I felt I needed to get home, and I turned it down. If I hadn't, I would have taken it,

because it would have been a hell of a deal. But anyway, so the problem existed, now the Korean war

come along, and the rule was that if you didn't—if you served less than a year, then you're eligible for the

draft. So all those guys that got out after about seven or eight months, were all drafted in Korea. In fact, I

had 11 months and 26 days, they equated it to a year, and let me out of the draft.



Hendrie: That was something that was lucky, but not planned.

Thorndyke: And my mother was in the background, insisting that she wanted a sole surviving son, but

no, the 11 months and 26 days got me out. And then I—

Hendrie: So then what were you going to do? So now you're back home?

Thorndyke: Back home in August. University of Minnesota, in the fall of '46, went from 15,000 students to

45,000 students.

Hendrie: Because of the GI Bill.

Thorndyke: The GI Bill, and the veterans coming home.

Hendrie: And did you have the GI Bill?

Thorndyke: Oh yeah.

Hendrie: Yeah, okay, so—

Thorndyke: And so one year of service, plus a month of—you got 12 years—or 12 months of—well say it

the other way. For every month of service, you got a month of college, and for being in service, you got a

year's worth of credit.

Hendrie: So you had automatic two years.

Thorndyke: Twenty-four months.

Hendrie: Yeah, automatically had two years.

Thorndyke: And what I didn't—I didn't register, or couldn't get in the first start of school, because it was

only about a week and a half, by the time I got out, that they started. And then the semester was up at a

Methodist College, and I didn't register at University, so I went to a Methodist college and studied physics

and math. And since I started at the center of the year, you're supposed to take 15 credit hours a month,



or credit hours a semester, I'm sorry, and the problems exist that I had to make up a semester, or go four

and a half years. They had, graduate three and a half years, or four and a half years.

Hendrie: Right, yeah, I see.

Thorndyke: Well, with the GI Bill giving me 24 months, I needed to manage it better, and so I was taking

19 to 21 credit hours. The government didn't object.

Hendrie: They don't care how many credit hours, they just tell how many years you—

Thorndyke: They would pay the extra tuition, and so I ended up making up a semester, and I graduated

in three and a half years, with 134 credits, 120 was needed.

Hendrie: Yeah, very good.

Thorndyke: So anyway, they also gave us credit for the service, the education, because I was in school

the whole time.

Hendrie: Yeah, in service, yeah.

Thorndyke: So anyway, then, I studied math, and after I got out—

Hendrie: Yeah, now what did you think you were going to do, you know, you were studying physics, why

did you pick physics? As opposed to engineering, well maybe there was no engineering at this school.

Thorndyke: Because—Well, no, that's right. It was a teachers and preachers college.

Hendrie: Okay, yeah, so you could take physics and math.

Thorndyke: Right, and math. And so you get out and then you start looking around for a job, and there

were not a lot of jobs, and I started working for a neon sign company that wanted to get into the

electronics business, and so that's why—we started making composition resistors, specialty type stuff,

and I worked for them for three years, and come to the realization that, with the boss and his teenaged

kids, that there's no future. And of course the wife was after me also—



Hendrie: This was going to be a family—this was going to be a family business, no future here with me.

Thorndyke: So as such, I got acquainted with the—I mean, I started going to night school at university,

for enlightenment courses. I was—went over there and started learning about landscaping, and bushes

and stuff. And I met a guy there that I got friendly with, went fishing a couple of times, and he was the

head recruiter for Univac.

Hendrie: Now had Univac already purchased ERA by this time, or Remington Rand? Remington Rand

purchased Univac, and then they acquired ERA.

Thorndyke: Yeah, it was in the process, and so—

Hendrie: Okay. So it's still sort of like ERA was, but it's almost—

Thorndyke: But it was still Remington Rand Univac at that time, and so he was a recruiter, and so he

wanted to recruit me, and I wanted a good job, rather than a—

Hendrie: Making components.

Thorndyke: Yeah, right.

Hendrie: But the components sort of related to your physics background, I mean you could—yeah, okay.

Thorndyke: And so we, you know, we had good business going on it, and, but I left, when they were

Univac, and—

Hendrie: Now, were you married yet?

Thorndyke: Oh yeah, I was married in the last year of—I was married in '49.

Hendrie: Ah, in the last year of college, okay.

Thorndyke: And so as such, why, I got into a group that was working in government explosives.



Hendrie: Now I don't understand there being government explosive work, even if you think of it, this is

really still ERA, not Remington Rand or Univac.

Thorndyke: Well, and, but it was Remington Rand, and ERA got by, by bidding [on] all sorts of contracts.

Hendrie: Yeah, it was a contract engineering firm.

Thorndyke: Right.

Hendrie: You did the engineering and then build it and deliver it.

Thorndyke: And so they bid [on] an electronic fuse for bombs or missiles, and rather than a mechanical

fuse—

Hendrie: So this is not—now this is not a proximity fuse, like they had in the war, this is a different kind of

fuse.

Thorndyke: No, it used a barium type piezoelectric crystal, which, you know, when you stress it, [it]

produces a voltage. And so, and then that ended up with an electronic detonator, rather than a

mechanical detonator.

Hendrie: Ah, so the piezoelectric crystal was a pressure sensor, which then produced a voltage, which

then you could put a tube in, and I mean, there was—put a little electronic circuit in, it would amplify it and

then fire off some sort of detonator.

Thorndyke: And what we used is, we used a capacitor as a battery, and used neon tubes, and so what

you'd do is, you'd fire a neon tube, which then would short the capacitor into the detonator, and as such, it

was so much faster than a mechanical fuse. A mechanical fuse, one of the problems was, if a Mach 3

bomber is flying 3,300 feet a second, well a mechanical fuse may take a tenth of a second or more to get,

by the time it mechanically moves, hits the striker, the explosion starts, you may be a tenth of a second

before you've got the full explosion. By that time, you're 300 feet downwind, or downstream, you're—and

so as such, the piezoelectric, as soon as it touched an aircraft would—we had a six inch cube, and so you

didn't travel—

Hendrie: That was your form factor that you had to put it into.



Thorndyke: Right, with five pounds of HBX, which is about 25 pounds of dynamite, and what happened,

they would fly ahead of the aircraft, and mortar, they'd take out this cone, of 200 of these five pound

devices, hoping aircraft would run into one of them. If it did, you shot it down.

Hendrie: So this is for antiaircraft…

Thorndyke: For antiaircraft.

Hendrie: …missiles.

Thorndyke: On the Bomarc and the Nike-B missile, used a cluster warhead they called it. Because at

that time, the way you intercepted an aircraft is you’d track it and let it go by and then shoot the missile

up. The missile, at the time it merged with a target, it flew an Archimedean spiral around in front and then

detonated all these devices.

Hendrie: Oh, really?! It was designed to do—that’s pretty sophisticated.

Thorndyke: Well, that’s the only way you c—because you lost it in the radar clutter. And you didn’t have

any guidance on it. So soon as you lost the radar clutter, then internally it just threw an Archimedean

spiral and flew ahead of it and detonated.

Hendrie: Yeah, I don’t know what an Archimedean spiral is.

Thorndyke: Oh, _______ it starts out at decreasing radius all the time.

Hendrie: Oh, okay. That’s what it is. Okay.

Thorndyke: Yeah, that decreasing radius. So my job was a—there were two of us on the designing of

the circuit using these different voltage breakdown [characteristics] of neon tubes. But then we ended up

having to encapsulate it to stand the shock. Because you had a hell of a shock on a mortar tube that

discharged and sent you out into the area. But also the electronic detonator was so sensitive. You rub

your clothes and touched it. 99 percent of the time it would explode.

Hendrie: Static electricity.



Thorndyke: From static electricity. Not a lot. I think it says that a .001 capacitor at five volts or less

would explode it 99 percent of the time.

Hendrie: Wow.

Thorndyke: It was sensitive as hell. Now, the problems were that the mechanical fuse has manuals

about that thick saying that here’s all the things you don’t do, if this happens, don’t do this, this and this.

There’s no such thing for electronic fuses.

Hendrie: Well, this is a brand-new thing.

Thorndyke: You got to kill a mess of people before you write those.

Hendrie: Yeah, you have to write them before all the people that could write them get killed <laughs>.

Thorndyke: Yeah, well, like the aircraft. There were accident reports. There’s a thing, well, don’t do this

or this and this.

Hendrie: Yeah, yeah, right, you fix the airplane.

Thorndyke: So I was out at Aberdeen Proving Ground, and my job was out on testing. And they

dropped one of my fuses, broke the connector. Now, the turnaround time is about four months by the

time you can send it back to St. Paul and you ended up having to buy special trucks that could carry

explosives, repair it, bring it back. And so I got out the soldering iron and soldered the damn connector

back together again. <laughs> Well, you say, well, I’m smart enough. First thing I did is I got the

soldering iron hot and then I shorted the contacts together so it wouldn’t become an antenna, number

two, made sure everything was grounded and there were no sparks or anything else. And then I soldered

it back together again. And then finally you kind of get back home. You come to realization that that was

not the smartest thing you ever did.

Hendrie: Because you thought of everything you could, but you might’ve missed something <laughs>.

Thorndyke: Well, yeah, then you turn around and says the, well, as an argument, if you have a dud shell

on the old unit, then you set it in the blockhouse for 24 hours on the misfire. Well, one of our mortars

misfired and it kicked it up about ten feet in the air and it fell back. Now what do you do? Well, the

argument is [the] reason you use that mortar is a g-force. So we had a weight that come down. Has a



spring. And when it did, it come back up and it rotated the detonator underneath the explosive chain.

Otherwise, the detonator setting over here in the side, it went off. Nothing went off, only when it rotated

around and through it. In the airplane, they had the propeller to spin it and meet—it’d bring that around to

where, when you hit it, would go through the lead explosive and the booster charge before it hit the main

charge. So questions are now is it armed or not, is the looking glass green or red. And so after I says,

well, look it, it’s only got a capacitor, doesn’t have a battery. And the capacitor’s got a load on it. And the

system was only active—from the time you disconnected the power, it’s only active for about four

seconds. And after four seconds, if you didn’t hit an aircraft, it detonated itself because you don’t want

live ammunition floating around. I says, well, give it a half hour and that capacitor, by leakage, is

discharged. And also we’ll go out. If it’s green, then it’s safe anyhow. And so after half hour, I crawled

around, looked at it and found a green.

Hendrie: What do you mean by green?

Thorndyke: Well, it’s safe. It…

Hendrie: It hadn’t rotated.

Thorndyke: …hadn’t armed, right.

Hendrie: Oh, it hadn’t rotated.

Thorndyke: Didn’t have enough g-forces to rotate. So wasn’t armed. It wasn’t lined up. Now, the old

rules say that, after a day, you put a box over it, you go couple hundred feet, you drag along. Well, this

cube [ph?] rolled out of the box. And so after about two times, I says, “Turn the box over.” I just picked it

up, placed it in. And we went over and got ___________________, put a mess of Primacord around it,

blew the damn thing up. But there’s no rules written.

Hendrie: <laughs>

Thorndyke: And so anyway, about that time, then the group I was in…

Hendrie: Well, you answered one question that I—was it’s just a capacitor. And that fires it. I was trying

to figure out, but you mentioned, how in the world a capacitor get charged. It’s connected until it’s fired.



Thorndyke: Yeah, so the aircraft—soon as you plug it in, they have the aircraft adapted for a connector.

And first thing you do, when you get ready to dump it, you put the power on, you charge it up. And it only

takes a couple seconds. So you don’t want that thing charged on the aircraft.

Hendrie: So these are antiaircraft missiles carried by aircraft?

Thorndyke: Yeah.

Hendrie: I’m just trying to understand the application here.

Thorndyke: No, they’re ground lines, all ground line stuff. Nike and the Bomarc were designed. Now,

what put us out of business is they put the nuclear warhead on the aircraft units. So they had nuclear

explosives on the…

Hendrie: On the Nikes.

Thorndyke: …Nike and the Bomarc. So it doesn’t make—you get close and it blows everything up and

it’s not a problem. So they had a nuclear warhead. They put this cluster warhead out of business. But it

was interesting, because I was out at Aberdeen Proving Ground. And they were trying every damn thing

under the sun, like they had equivalently of a Lazy Susan <audio glitch> we never had an accident, never

had an explosive. We handled a fair amount of the devices. So anyway we learned there. But the group

evolved into peripheral devices. UNIVAC’s in the computer bus—Eckert-Mauchly was out in

Philadelphia. Eckert-Mauchly designed a computer. The UNIVAC computer they designed Remington

Rand bought.

Hendrie: The UNIVAC I, yes.

Thorndyke: Yeah, and it was designed as only university professors would design in that they ended up

having all cascade voltages. From minus 300 to plus 300, they put in all of the DC amplifiers. And, as

such, any one voltage drifted, then everything quit.

Hendrie: Oh, because, yeah, it would move all the rest.

Thorndyke: Right. And so effectively you ha—and whereas the people from ERA ended up using pulse

transformers, everything is referenced to ground voltage. So after the vacuum tube, you run it through a

pulse transformer, the pulse transformer. Then the secondary has got ground voltage exciting the next



tube. And so, therefore, the ERA people were low-impedance designers. And the Remington Rand

people were very high-voltage, high-impedance designers.

Hendrie: So there was a totally different circuit philosophy.

Thorndyke: And a lot of the radar circuits were low-impedance circuits, emitter followers and that sort of

stuff, diode logic. And a lot of the technology for computers come out of the pieces of the radar and then

pieces of automatic Teletype. Eccles-Jordan’s flip-flop came out of Teletype needs. And so, as such,

those two were the area. But ERA went down the road of low impedance. And so, as such—where

Eckert-Mauchly went down the road of high-impedance cascade voltages. One of the great selling points

in the UNIVAC was a panel about that wide and high that had about, oh, probably 35, 40 voltages. And

each one was a voltmeter of a particular power supply, and then they had lines on it on where it was with

respect to in spec or out of spec. And if, in fact, they found a unit went out of spec, then they’d kill all the

voltages. It would trigger a Polaroid camera to take a picture of the voltages. First thing you’d do, pull the

camera out and see which voltage drifted.

Hendrie: Oh…

Thorndyke: <laughs>

Hendrie: …that’s actuary. I mean, <laughs> that’s pretty clever.

Thorndyke: Yeah, they found a way to live with it. A lot of those circuits in the early computers with

_______________ were radar circuits, like emitter followers. And, as such, with emitter followers is in the

cathode.

Hendrie: Right, right, yeah, I understand that. But radars are fundamentally analog devices. I mean, so

you can use emitter followers for the power…

Thorndyke: <inaudible>.

Hendrie: …for amplification. But how did they do logic?

Thorndyke: Yeah, but the early computers were, to some extent, analog devices. You’re still using

vacuum tubes ________________ vacuum tubes. And then you did diode logic.



Hendrie: Ah, okay. So ERA used diode logic.

Thorndyke: And/or diode logic. And then you’d go back and reference to plate voltage. You go back to

the next amplifier. You go back up to voltage because if you go through the diode logic, you lose voltage.

And then out of that come an inverter circuit. I think the radar’s using inverter circuits off and on. The

problem with inverter circuit is they would lose a little bit of voltage on the output. The input versus output

was never at real voltage. And then the semiconductor started coming in. And Mr. Cray, and I think Jim

Thornton was the other person but I don’t remember that, got a contract from the Navy to transistorize a

computer. And it was not a full computer. But try to design a computer comparing magnetic amplifiers,

which the East Coast guys were in love with.

Hendrie: Yeah, because UNIVAC actually ended up building a magnetic amplifier computer. I never

heard the story why or how.

Thorndyke: Well, they’re in love with magnetic amplifiers. And in the meantime, Seymour was in love

with transistors. So he built a demonstration unit using transistors called Transtech. And that proved

that, yes, you could. Now, the interesting thing with—when the first transistors come in, now you got a

new technology. How do you use a new technology? You simply made a transistor duplicate a vacuum

tube.

Hendrie: Okay. You use the same, yeah, so you use diode logic.

Thorndyke: Pulse transformers, everything else.

Hendrie: A transistor is the amplifying element, and a pulse transformer get everything.

Thorndyke: Go back to real voltage.

Hendrie: Yeah, so it’s AC coupled, not DC coupled.

Thorndyke: So you could do that. But then I think Dolan Tolson [ph?] and some of his group come

across the area that, since the inverter circuit lost a little voltage, after so many, you had to go back into a

flip-flop to get back to regular voltage. Over time, after about two years, they developed ability for inverter

circuit to get back to real voltage. Or, to say, the 12 volts are what it was.

Hendrie: Now, these people you’re talking about, they’re working for UNIVAC…



Thorndyke: Yeah.

Hendrie: …ERA? Okay. These are people in the circuit group.

Thorndyke: And so, as such, now you start bringing inverters together forever without losing…

Hendrie: And you’re okay.

Thorndyke: …without degrading where it gets marginal. And that then through the whole s—allowed

you to junk the vacuum tube philosophy. And now you could go to an inverter circuit, the or-inverter or

and-inverter circuits. And…

Hendrie: And just keep going.

Thorndyke: …that was a tremendous advance.

Hendrie: And so you only go to a flip-flop when you need to clock something…

Thorndyke: Or sort.

Hendrie: …or synchronize.

Thorndyke: Sort. Flip-flops are the storage element. So it registers.

Hendrie: Yeah, registers.

Thorndyke: Right. And then, over time, as we reduce voltage, we find that you had to get rid of the

and/or diode logic. Where you used to send diode logic together and lose voltage, now you’re beginning

to reduce the voltage. Because the more you reduce the voltage the faster a transistor is. Doesn’t have

to swing so far. And so you keep lowering the voltage. We got down to five volts. I think they’re down to

about three volts or so nowadays. But by reducing the voltage, you have reduced the transition time. But

now you can’t go through a diode that’s going to drop a volt. Put two or three diodes together. All of a

sudden you don’t get anything out the back end. So we had to take only one set of diode logic. Then you

go to an inverter again. And so effectively now you’ve got, instead of dozens of transistors, you got

hundreds of transistor to thousands of transistors.



Hendrie: The diodes you were using back when there were tubes, these were not germanium diodes.

Were these selenium diodes? Or what kind…

Thorndyke: No, no.

Hendrie: …of paths were they? What kind of diodes did you have?

Thorndyke: They started with germanium.

Hendrie: Okay. You had germanium diodes.

Thorndyke: But they went to silicon.

Hendrie: Okay. Then they went to silicon.

Thorndyke: And they’re big diodes.

Hendrie: Hm?

Thorndyke: They’re about half the size of a head of a match.

Hendrie: Yeah, yeah, sure, I remember the little germanium diodes.

Thorndyke: And so then that effectively then let Seymour come out with the NTDS computer and a

AN/SQ-17.

Hendrie: But wasn’t the 624 the first one he did? Or would that become the AN/SQ-17?

Thorndyke: I don’t remember those. The only thing I come into in ‘5—’58 I think it was.

Hendrie: When did you get to UNIVAC?

Thorndyke: I started in ’54 to ’60.



Hendrie: You started in ’54…

Thorndyke: I started in ’54.

Hendrie: …at UNIVAC?

Thorndyke: Right. And about ’56 or ’57, people started leaving and going to Control Data because

UNIVAC didn’t solve the St. Paul, Philadelphia problem.

Hendrie: Can you spend some time?

Thorndyke: Yeah.

Hendrie: Tell me about what that was, because you were there. I mean, you were not at a high level

necessarily, but you knew what was going on.

Thorndyke: No, we’re affected. When Philadelphia got in charge of everything, they would stop

programs in Minneapolis. I used to spend three weeks to a month in the library. We didn’t get fired.

They just stopped the programs. Philadelphia in charge, they just turned everything off. And then all of a

sudden that started not working, because they’re late. And then we got turned back on, on overtime, to

catch up on the programs that Philadelphia had killed. And so I remember Eckert came in, and I had

spent time magnetically designing a part. UNIVAC had developed a file computer. At the heart of it was

a magnetic drum at 12,000 rpm.

Hendrie: Oh, wow, that’s very fast.

Thorndyke: And they wanted to speed it up to 24,000 rpm, and so we ended up getting a 24,000 rpm

drum. But they never got the circuits to speed up two to one. See, that was still a vacuum tube back in

those days.

Hendrie: And so was this a drum—I know ERA made some money, got good at making drums probably

from their code-breaking machines. They needed them then.

Thorndyke: And, the first drum they built, they simply wrapped magnetic tape around a drum.



Hendrie: Really?!

Thorndyke: That was the first drum…

Hendrie: That ERA built.

Thorndyke: …that ERA built and built for the FAA. The FAA bought this magnetic drum with tape

around it. And, of course, then the heads were far enough away. So you glued it on. That proved -

feasibility. Then they found out you could mix up oxide and pour it on and then grind it back off again,

machine it off. And so you had a couple thousand-inch of magnetics. The first drums were clovenly

[ph?], in hindsight, a core type. You ended up with a clock track. You wrote. All the data was a pulse.

And so these pulses were individuals. They were not strung together at all. So you had a bit-alterable

drum, and so it is effectively a core memory. The clock tracks. You read them up. Clocks tracks, read

them out. And so, as such, the rumor has it, before my time, that IBM came in. And they got interested. I

guess young Watson got interested. And so they bought a license apparently on magnetic drums.

Hendrie: I know because the 650, one of their early machines, had a magnetic drum in it.

Thorndyke: And, as such, then they came back and said, “Well, how the hell do you dress a drum? We

got drum. But what do you do with it?” So they started telling them. And the rumor has it that ERA

designed I think the 605 for IBM, and they didn’t get paid for it. They just designed it because they

thought they were going to sell drums, but IBM bought a manufacturing license.

Hendrie: <laughs> That didn’t work.

Thorndyke: Well, that’s part of the reason Norris was always spastic about IBM. He’s always spastic

about IBM, because he thought he got snookered I think. I never heard that. That’s just an observation.

But I know that people had Selectric typewriters. He’d get one of them and he’d write down, “I do not

want any IBM printed material coming to my desk.”

Hendrie: Oooookay.

Thorndyke: <laughs>

Hendrie: That’s pretty strong.



Thorndyke: That was way back early on.

Hendrie: Wow.

Thorndyke: And later on, when we’re in the disk business—this is jumping ahead but they can

straighten it out. At the time we started developing disks, after the tapes, we had a disk developed for

Seymour [Cray]. We spent a lot of money developing it. And IBM announced I think the 1301. It plays a

disk pack that stored about two megabytes. And as I looked at it and knowing what Seymour’s doing—

because the supercomputer people were always five years ahead of what IBM evolved to because of IBM

conquering for the business market which had small records and this sort of stuff. The scientific guys

wanted big records and fast and a lot of data. Your payroll data is small, lots of small records. So data

array is not the problem. Access is a problem. And so the tape to disk gave us access advantage over

tapes very high. And so, as such, this is jumping ahead but we can come back to it, my budget, in ’64,

was $1 million in R&D and it only had about 20 guys.

Hendrie: Wow.

Thorndyke: Had a million dollars. And, as such, we were deep into Seymour’s disk. It’d come out in

’65. And here’s this IBM disk pack. And our big device was sold for $400,000. You’re not going to put it

on a small computer. So after we sat around then, I said—in order to keep the program on schedule, we

changed everything. We had to spend $4,000 a day. And there’s 250 days at 4,000. That’s a million

dollars. And so, therefore, he said, well, he couldn’t afford to get competitive bids. You selected who you

wanted and the vendor, and you simply went out. And since engineering dollars, there was not a mana—

the purchasing people didn’t like it. Because they liked to play off, trade off. They said, “You don’t have a

choice. We’re going to Alcoa for this casting.” Well, we got another guy says, “You don’t understand. It’s

my money. We’re going to go to Alcoa casting because Alcoa is the best people to make a casting.” And

so, as such, that’s the way we spent our money. And we started looking at that IBM device. And so I got

the guys around. I says, “You know, if we slowed this thing down to $3,000 a day, then $15,000 is two

weeks,” it’s actually probably three weeks, “Three weeks, we’d have enough money to buy an IBM

machine.”

Hendrie: And then you could go see what they’re really doing.

Thorndyke: Evaluate what we got. And so I went to Tom Camp and Camp said, “I wouldn’t touch it with

a ten-foot pole. There’s no market for disks. All we’re going to do is we sell tapes. We’re going to sell

tapes.” I said, “Tom, we want to spin our technology that we got down into this new market.” “Oh, no,

there’s no market at all, no OEM market.” All he could think was OEM. But since he didn’t have—no one

was out selling this, then he had no reason to believe that it wouldn’t be sold. And I says, “Well, I’m going

to go to Norris with it.” I’m two levels below him. And I says, “Fine. I’m going to go over and talk to Mr.



Norris about it.” And he said, “Well, you do what you need to do.” Because engineering technically

organizationally reported to him. But technically, engineering did not report to him. We had Bob Perkins

who was on Norris’ staff, and he was really the chief technologist. So he arranged for me to see Norris.

So I go in there, and I had my pitch. And I told him w—

Hendrie: I mean Norris is an engineer.

Thorndyke: Right. And he listened to a sales pitch. And so I come in and I says, “You know, we got all

this technology for the big unit. And like in computers, Seymour developed a supercomputer. And out of

that was spun about seven different computers all using same technology of spinning it down.” I say, “We

know how to machine disks. We know how to build servos. We know how to sector disks. And this, at

400,000, will never sell on your volume computers. And Seymour’s going to sell on the big computer.

But your business computer, small, 3300, 32, 31, needs a small disk. Because IBM’s pioneered a small

disk, and access time is critical.” And he says, “What do you want to do?” And I says, “I want to buy

one.” And he says, “What are you going to do?” And I said, “We’re going to find out what it is. We’re

going to evaluate it and find out what it is.” He says, “Then what?” And I said, “Then we’re going to—I

want to produce a device compatible with IBM’s disk pack.”

Hendrie: Yeah, uses their pack.

Thorndyke: “Just like the tapes, just like tapes, now I want to exchange business packs with IBM.” He

said, “Hell of an idea!!” signed a WCM.

Hendrie: <laughs>

Thorndyke: So I come back. And then, afterwards, why, then Tom started to pitch that he invented it

and sent me over and everything else. Camp, he was that type that his ego was very high. And,

therefore, since product didn’t exist, he wasn’t interested. But the product did exist. Now, what happened

out of that product is we were very far ahead of the market. But rather than get into that, let’s back up

with ______________.

Hendrie: Okay. So we’re going to go—when we go back, we’re going to go back to when Norris said,

“Okay. Go…”

Thorndyke: We’re going back when we had the explosives.

Hendrie: Yeah, let’s go back to after the explosives.



Thorndyke: Then we started studying peripherals for UNIVAC. And, in that, one of the things that we

started looking at is the mechanical guy designed a voice coil air valve. It’s an air valve driven with a

voice coil.

Hendrie: And why did they do that?

Thorndyke: Because we’re interested in moving tape and a vacuum capstan. And the problems are that

a voice coil’s low mass. And you either had vacuum or pressure, vacuum or pressure. So you switched it

back and forth. And you could build it very, very tight together. And so we had a valve that went from

fully closed to fully open or effectively from full pressure to full vacuum in 1,000th of a second.

Hendrie: In a millisecond?

Thorndyke: Little less than a millisecond.

Hendrie: Wow!

Thorndyke: Because as soon as you started moving, you started getting a ramp. And that was done at

UNIVAC. And then Eckert-Mauchly came in, or, J. Presper Eckert.

Hendrie: That was done…

Thorndyke: UNIVAC.

Hendrie: …in Minneapolis?

Thorndyke: Yes.

Hendrie: Okay. You guys did that.

Thorndyke: Yeah, and so Eckert came in as chief engineer and chief inventor and said, “Awww, that’s a

bunch of crap. You know, after all, you got to use my version of how you move tape <inaudible>.” So we

scrapped the program. But we learned enough that you could move tape with it. And it’s faster than

anything else, because a pinch roller accelerated the tape in about 1½ to 2 milliseconds. But when it did,



it yanked it so hard that you had burn marks on the tape and you also kind of stretched the tape and then

it rebound. Because when you hit it so hard, the tape is elastic.

Hendrie: Yeah, course, it’s elastic.

Thorndyke: And so it sits there and rings on you. However the vacuum capstan has got a faster start

time but a slower acceleration, because nothing pinches it. It’s just sucked down.

Hendrie: Just sucking the tape down on the capstan?

Thorndyke: Right. And the capstan had a series of slots in it. We moved slots and drilled holes in the

bottom of it. And you keep those distant because the speed of sound over the vacuum is 1,100 feet a

second. And so, therefore, now you come down and say, well, a millisecond is one foot. And by the time

that you get the vacuum, unless you got accumulated very close, you had a long line. That line will go to

zero pressure while it’s propagating. So you got to have accumulator within a few inches.

Hendrie: Now, by accumulator, you mean…

Thorndyke: A hole, reservoir.

Hendrie: A reservoir, yes, of course.

Thorndyke: And so that reservoir then is trickle charged from the main unit. But it effectively then—

when you suck it out, that is providing the air for the first few milliseconds or less so that we can

accelerate the way we wanted to. And all that work was done at UNIVAC, canned at UNIVAC, scrapped

at UNIVAC. And so we learned a lot. They also built a tape unit.

Hendrie: So from this vacuum capstan b—y—when did—that must’ve resurfaced at some point because

capstans became the standard.

Thorndyke: It resurfaced at CDC, not at UNIVAC.

Hendrie: Ahhhh, ohhhhh, now I’m getting it. This was done at UNIVAC…

Thorndyke: At UNIVAC.



Hendrie: …before CDC. Now, was this before CDC started?

Thorndyke: It was simply scrapped, and Eckert come in and killed it. And they also designed a tape unit

and learned how to design a tape unit because mechanical engineers design it, not electrical. And, as

such, it impedes mass inertia, the reel of tape, and acceleration. And, the problem with magnetic tape, as

you accelerate the reel, if the acceleration is too high, the tape slips because the tape is wound up. It’s

wound all the way out. Well, if it goes to zero tension someplace in the center, as soon as you accelerate

the hub, there’s nothing to accelerate the outer tape because there’s no compression. So, what happens,

it’s called cinching. So it takes that outer layer, puts it in the folds until, in fact, there’s a, now, continued

connection to the outer layers that accelerate the outer layers. So you can’t accelerate the tape too damn

fast, the reel of tape.

Hendrie: Okay. I understand. Okay, yeah. Okay. Yeah, so inside, yes, it could accelerate if it’s feeding

the tape or even if it’s, yeah, if it is pulling tape, yes, it will cinch up the tape inside without the outer edge

moving at all.

Thorndyke: Yeah, and <inaudible>.

Hendrie: That makes sense.

Thorndyke: And so you wound that tape. Now, you couldn’t take a lot of tension on it, but you had

enough tension that if you had acceleration controlled then you could accelerate the tape back and forth.

That’s what a loopbox is for, so that loopbox is a storage area so you don’t have to have the acceleration,

so shutter the loopbox and the more acceleration you’ve got to have in the tape to put tape down there.

Hendrie: Tape down there, because it’s already moving by the head at full speed.

Thorndyke: And that loopbox decouples the tape speed from the reels, the real tape speed.

Hendrie: The reel speeds, yes.

Thorndyke: So, anyway, you thwart all that over there. Not only that, but also at UNIVAC we started

exploring discs and finding out that I ended up having to be able to flight heads on a rotating disc, and we

built a disc device that had 39-inch discs with heads that were flaying on the surface.

Hendrie: Now, who did you build this for? For Seymour?



Thorndyke: Internal.

Hendrie: But who?

Thorndyke: Just internal.

Hendrie: And you’re just seeing what you could do?

Thorndyke: Well, we had a research program, and of course that got stopped by—when Acker [ph?]

come into town. That’s when it stopped and started and stopped and started, so here we had all this

experience with discs, and then UNIVAC was formed—I’m sorry, CDC was formed and they moved out,

and as such, the people that went over to CDC were predominantly from NTDS.

Hendrie: Because Seymour was going to go- they were going to go build a computer CDC. See, that was

the original plan, and so he took his...

Thorndyke: So, they picked and cherry-picked him, and pretty soon the UNIVAC management said,

“Well, what we got to do is we got to send people over there that are new to NTDS.” So they come down

to commercial and sent my boss over, Jay Kerschaw [ph?]…

Hendrie: Commercial is—this is still in Minnesota?

Thorndyke: Yes, in commercial.

Hendrie: But commercial.

Thorndyke: But the group that was doing all this research on different peripherals and everything—so

they sent my boss, who then recruited me to come up and.

Hendrie: What was your boss’s name?

Thorndyke: Jay Kerschaw. And Jay went over and was a very unique person. He should’ve been a

college professor; he’s that good at teaching and was also—had a very, very good mind on what you

could do with computers, and soon as he saw what was being developed by NTDS he went back and



said, “Why in hell aren’t you using that NTDS technology to put in your commercial computers? It’s so

damn much better.” And, oh, no, no, no, they were against that, because they didn’t invent it.

Hendrie: Now, so there’s a commercial-computer group and the NTDS group at UNIVAC. This is just

before CDC disappears. And what was the commercial-computer group doing? I know you were working

on…

Thorndyke: Well, they were...

Hendrie: …peripherals, but what was the rest of the commercial group doing?

Thorndyke: They were doing a kind of...

Hendrie: Were they doing the 1103 and the 1105?

Thorndyke: No. The commercial people were working on a...

Hendrie: I know they had a...

Thorndyke: …UNIVAC II, it was called.

Hendrie: They’re the people that were...

Thorndyke: And a file computer.

Hendrie: I thought the file computer was done in Philadelphia. No?

Thorndyke: No. That was St. Paul, from A to Z.

Hendrie: It’s St. Paul, A to Z.

Thorndyke: And they were building one a day, and the drum was confiscated by Sperry Rand to build a

drum, and Sperry Rand was having trouble building it, and of course St. Paul people felt it was a plan for



them to not build very many drums, so all of a sudden St. Paul has got this tremendous inventory of parts

and no drums. And I think that’s what drove Norris out.

Hendrie: So, who was doing this? Who was building the drums?

Thorndyke: Sperry Rand.

Hendrie: Sperry Rand. Now, at Remington it was…

Thorndyke: Prior it was Remington Rand.

Hendrie: So Sperry, Remington, Rand and UNIVAC were all—and ERA were all together?

Thorndyke: Right, so they were doing the production, except they weren’t producing it, and, of course,

the rumors were that, well, as long as they didn’t produce it, St. Paul couldn’t deliver, and if St. Paul

couldn’t deliver, then in fact, Philadelphia felt pretty good about it.

Hendrie: Philadelphia looked better.

Thorndyke: Philadelphia in charge and then UNIVAC and St. Paul’s in charge, so that was bounced back

and forth continually.

Hendrie: Really?

Thorndyke: Oh, yeah, and one of the other reasons that finally Norris got sick and tired of it.

Hendrie: So, now, did UNIVAC—so in Philadelphia they did the UNIVAC I, and then did the UNIVAC II

get taken away from them?

Thorndyke: Well, no. I think they funded it, but Jay said that the UNIVAC II was almost an abortion,

because they tried to keep all the stuff that the UNIVAC I had like the cascaded power slide and all that

sort of crap.

Hendrie: I see.



Thorndyke: But Dave Lundstrom [ph?] is far better to discuss that if you ever want to get into that. He

lives in Minneapolis yet, but, anyway, so we—and then I was out NTDS and I had all the peripheral in

NTDS and...

Hendrie: So that’s what you...

Thorndyke: …I gravitated into it, and...

Hendrie: What were the peripherals in NTDS, because it was a shipboard system?

Thorndyke: Well, they’re to be developed, but what you did is you also had to have a data center. You

got a hell of a big data center, and the bind exists that- and everything had to be designed for MIL

[Military Standard] E6E 16-400, and that says that you got to take a 50G shock.

Hendrie: Of course.

Thorndyke: And what that was, was...

Hendrie: In the data center?

Thorndyke: With a 10-foot arm that came in to a poured cement wall. You got your 60Gs or 50Gs, which

is to duplicate the firing of all the 16-inch guns at once. But the restriction is that’s also in there, it had to

go through a 25-inch-diameter hatch. Everything had to go through a 25-inch-diameter hatch.

Hendrie: That’s the standard for Navy equipment...

Thorndyke: That’s the standard, yes.

Hendrie: …because they build the ships with a 25-inch hatch.

Thorndyke: Submarine and everything else. I said, “Well, why we got to have a 50G shock in a

submarine?”

Hendrie: A battleship you understand.



Thorndyke: And also the thing says that in wiring you got to wrap the wire around the post twice and

solder it and that sort of stuff. Solder can only be an electric. It cannot be a mechanical connection. In

other words, you just can’t put the wire alongside the solder and use the solder to hold the wire. And then

there’s a 500-volt insulation test. I says, “Wait a minute. These are transistor circuits at 25 volts. What the

hell we got a 500-volt requirement?” Now you got a wire that’s got insulation for 500 volts and you’re

never going to have more than 25 on it. And so it was fighting that through, so we got through that and I

was in charge of all peripheral and including the video processor. And the video processor, we had some

very high-speed I/O on the computer, and that high-speed I/O was a—normally in there you drove it to

ground and let the resistor pull it back to rail voltage that you send data in and out. Well, that RC time

constant is slow, so what they did is they produce a special circuit that would drive power both ways, so

you ended up having affluently a PNP and NPN.

Hendrie: Push-pull circuit.

Thorndyke: Well, the problems were that that was plugged into the computer without any documentation,

and so I’d found that I could go into the computer and hook into it and put a whole series of toggle

switches on, and the toggle switches, since it drove to ground, then I could send out function codes to my

equivalent while they’re still working and I could get a function code, and otherwise I had to wait until the

computer was available to me to tend out a function code. Instead, I just plug it in and could fake it,

except one day they plugged it into that push-pull circuit.

Hendrie: Wrong place. Uh-oh.

Thorndyke: And there’s a fire.

Hendrie: Really? Wow.

Thorndyke: Now, Seymour built that computer in a casket, so it was 30 by 30 and blowers underneath

and blow air vertical, so started a fire, and of course those circuits were at the bottom and it started

blowing and it started burning. So we started burning up the computer and they couldn’t put the fire out

because the fan was blowing up and you couldn’t get the fire—you had to take the skins off and

everything else to put it out.

Hendrie: Oh, my God.



Thorndyke: So, there was about $50,000 worth of damage. Course, I got my butt kicked for that, but

there’s no documentation that that channel is not to be touched, and it was word of mouth, except that’s

only computer word of mouth, not us other guys.

Hendrie: And so all the computer guys do but the peripheral guys didn’t.

Thorndyke: Well, and then beyond that the Navy doesn’t want anything that burns on board ship. All of a

sudden they said, “What the hell do you mean? You designed this with a—your printer-circuit boards got

epoxy that burns?” “Yep.” “No, you can’t have that.” So, effectively it was lucky for UNIVAC in hindsight.

Hendrie: Because they found out early.

Thorndyke: They found out that you got to end up paying attention to the fire-resistance capability, and

so, anyway, the video processor of the radar came in, and the program was so classified that how do you

spot a—how do you get a digital reference to an analog trace? Well, what you do is, well, you’ve got this

trace of noise. All of a sudden you’ve got this blip, which says the aircraft. Effectively now you draw a

blank area around that blip, so I digitized _______ the ones, and everything above the unit is zero. Then,

over time, the next sweep you find out if it moved, and then you compare the two ones and if the ones

overlaps the zero.

Hendrie: I understand. You have two words in the computer with zeroes and then a couple of ones and

zeroes, and there’s a certain place in the word and if the...

Thorndyke: From the index mark to that, and if it moves, no, in fact, you’ve got a move. Otherwise, after

time you say, “Well, I’ve got a fixed object, a radio tower or something.” Well, pretty soon you eliminate

that. That doesn’t move. You move, but that doesn’t. In other words, the aircraft moves but that doesn’t.

So, anyway, it’s so classified that I ruled myself not eligible to see it. I didn’t need to manage a crew by

getting that deep into it, and so as such then I could keep other people that wanted to look at it. And the

reason we had that push-pull circuit on the display is then it would go around the display and get it over

there fast enough. And so, that effectively then, as a result of...

Hendrie: Would get it from the display, you mean, to the...

Thorndyke: The computer to the display.

Hendrie: The computer. This is where the computer is driving the display?



Thorndyke: Right.

Hendrie: But the other thing you were talking about was radar coming in and digitizing it and telling the

computer whether—what the radar is saying. So they’re two different things.

Thorndyke: And it stored it in the computer memory, and then out of that from this very high-performance

display, video display, and then the guys quit. They went out and formed a company called Data Display,

a great—back in about ’50, when ERA had formed, they were outbidding any contract they could, and this

is all hearsay, because I wasn’t there, but they had found that if you take a load and release it quickly,

then you will find that there is an acceleration, and as such that acceleration then tells you the weight.

And if you process that and take a compound out, you get the weight. And, as such, so they proposed to

the people up in the iron ore of Duluth that they would make a device that would weight the railroad cars

as they were humped across rather than stopped and balance-scaled. And so they got a contract and

they instrumented and took it up. They weigh a car on the balance scales and then hump it across and

weigh it and got correlation, and as such they found that the people that were buying the iron ore owned

the balance scale and they tended to have a lower weight than the electronic—the moving scale. And so

that was known as the Great Train Robbery, because all those guys insisted that it had to go across the

ERA scales, and then later on it was proposed that they start weighing trucks on the fly, but they decided

they didn’t need to get into that business. I don’t know if they tried to sell out or what. I have no idea

what..

Hendrie: But that was one of ERA’s just—they did engineering jobs like that.

Thorndyke: All sorts of fun things.

Hendrie: All sorts of weird stuff.

Thorndyke: There was also a bore-hole camera for oil wells, and I don’t know what that was; I just heard

about it. Anyway, so that was that invented group at UNIVAC, and...

Hendrie: So, could you tell me—we left off the last tape with the display, the output display from the

NTDS computer and that somebody had went off and started a company.

Thorndyke: I can’t think of his name right now. I’ll get it one of these days. I almost see it. Anyway, he

took good engineers with, and they developed ability to form letters and using a CRT in a program to

write an A or B or C or anything else so effectively that you could print. You could read the data, and it

was electron-beam-driven, so therefore you make pictures and anything else you want to, and that was—



when you see the 6600 with the dual ports on the 6600, they had that derivative, that software that would

do all the writing.

Hendrie: That was the same.

Thorndyke: And that’s why it was spun off or it was taken off. See, UNIVAC really didn’t try to protect any

technology flow, and, well, even in CDC I couldn’t afford the patents. There was a certain budget for

patents, of which 95 percent of them went to Seymour, and so we in our stuff, we made it public domain.

We announced it, talked about it and it became public domain. Once it became public domain, now in fact

nobody can patent it on us.

Hendrie: So they can’t patent it on you and come back at you, but...

Thorndyke: And four years from now we’re not going to do it, and the only problem with a patent: It’s

worthless unless you’re willing to defend it. Well, it costs money to defend it, and if you’re talking a little

company against big pockets, you can’t win; you got to give up. So you shouldn’t even start it, and that

was my philosophy. It costs me as much for a patent as it does an engineer, so I couldn’t afford the

patents.

Hendrie: So then it costs you part of an engineer to do all the claims and write the patent.

Thorndyke: And Jack Rabinow, who ended up having 250 patents, one time was head of the Bureau of

Standards, and Jack had his own personal patent attorney, Joe Genovese, and Jack then would get

every new patent from the patent office. He’d read them and he’d go, “Hey, Joe, come in here. They

missed this claim.” So then he would end up putting the patent out, and that’s where he got his 250, but

he was very inventive. Back in the ’30s, one of the problems is the clock in the car, well, it’d need to be

removed and speed it up or slow it down until it was on. Well, that cost money, so what he invented was a

1,000-to-1 gear ratio that hooked on to the end of the timer spring, and as you speeded it up then it

tightened the spring. Or, if you turn it backwards, too, because it’s going too fast, then it released the

spring at 1,000 to 1. Then over time incrementally as you adjusted it, incrementally you got it absolutely

dead on. So, you didn’t have a few minutes’ flow. He just tweaked a little bit, so you tweaked it, and right

away they said every time you find it slow, just tweak it one way or the other. And so by adjusting it, I

think he said he got a penny and a half royalty.

Hendrie: For every one of those? That’s pretty good.



Thorndyke: But he was very inventive. There’s a thing called a magnetic particle clutch or brake. He

invented that.

Hendrie: Really?

Thorndyke: Yeah. So he was very inventive, and later on we’ll go into one of the inventions that we

actually used on him. So, anyway, the...

Hendrie: So, your...

Thorndyke: There were a lot of spinouts, and so they pulled us out of commercial and sent us up to

NTDS. And then I left NTDS and the Navy had told Control Data that no one in NTDS is to be recruited,

but the problems are that you can clear your own accordant goal. They just can’t recruit, and so I knew

the crew and so I went over and interviewed, because I could see even the manager of NTDS that I was

getting too far into management and I wanted to get more experience in design effort before I—because I

was a manager and I’ve probably been higher up, maybe, but I didn’t think I had enough design

experience.

Hendrie: And so what year would this be?

Thorndyke: That was in the middle of July of ’60.

Hendrie: July of ’60. So you’d been working on the- you started working- you moved to NDTS in, what,

the middle of ’57, ’58?

Thorndyke: Probably about middle of ’58, and—let me back up. We’ll leave that one hang. Let’s go back

in some of the things we did in the commercial area.

Hendrie: Be very aggressive [ph?] then.

Thorndyke: One of the areas that we developed was a peripheral processor card-to-tape, card to

magnetic tape, a card reader to magnetic tape, a paper tape reader to magnetic tape with a plug board

and then a tape unit and, as such, that was sold as part of UNIVAC to Parke-Davis, and so I was not a

programmer, but I had part of the integration and the problem that we had at Parke-Davis is every

Monday morning at nine o’clock the tape unit would run away. It would end up master-clearing [ph?], and

about 10 o’clock the problem went away for the rest of the week and Monday morning it’s bad again, so



I’m flying Parke-Davis every Sunday afternoon and in that plant in the morning and trying to figure out

what the hell’s going on.

Hendrie: What’s going on?

Thorndyke: And then after it quit, you got to reset everything and reload and start all over again.

Hendrie: Now, where is this physically? Where is Parke-Davis?

Thorndyke: Where is Parke-Davis? In Detroit.

Hendrie: In Detroit.

Thorndyke: It’s a drug company.

Hendrie: I know it’s a drug company; I didn’t know where they were.

Thorndyke: So I’m down in the cafeteria and the group of us got together, and part of the group was the

health area, the medical area for interviews or for hiring, new-hire screening. And I think, I don’t know

what the hell goes on here at nine o’clock in the morning, but something’s going on. Now, that’s when we

turn on the X-ray machine. So, you turn on the X-ray machine from the computer room. Where are you?

She said, “We’re just a wall behind the computer room.” And I said, “I’ll be damned.” So I was introduced

to EMI/EMC, and...

Hendrie: Oh, my God.

Thorndyke: So I said, “Oh, my God.” So I went out and bought a Compton-Mully’s [ph?] transformer and

plugged it in. That’s before you had any line filters or anything, and then we put—as I remember, we put

aluminum foil, just hung aluminum foil from the walls, and I never went back, but I learned EMI/EMC.

Hendrie: And you never forgot it.

Thorndyke: So, now, well, the other thing that I remember, on the Lodge Freeway, it was nine lanes wide

someplace on that freeway in Detroit. And they had a sign out says, “If you have your car stall, stay with

it. The average life of a person crossing traffic is nine seconds.”



Hendrie: Oh, my goodness.

Thorndyke: Well, you got nine lanes and you can’t find a space that you can run across nine lanes

without getting hit, so, average life, nine seconds.

Hendrie: Nine seconds. That’s pretty good.

Thorndyke: But, anyway, so then as we started—and I started then putting in line filters and stuff in

equipment. When I went to CDC, one of the requirements was that every single peripheral had to have a

line filter. And that makes cost and all that sort of stuff. Problems are the problem went away. We went

against other people and we’re on the air. They’re off the air. They hit a line transfuse, line-voltage

transfuse and they’re gone, and so Control Data’d built a hell of a reputation for our peripherals staying on

the air.

Hendrie: You’re just very reliable, because you take care of things like that.

Thorndyke: And they never equated it to the line filter. But, anyway, so then we got a contract at UNIVAC

to build the airlines reservation- I’m sorry, an airline and route traffic-control capability. Up to that time,

you called up on the telephone and you reserved the space over their control. Then you called the next

one and reserved a space, the next one and reserved a space, and so there are five control areas from

Indianapolis to Pittsburgh to Washington, New York and Boston, and they wanted to start the early

automation, and what that required then is that we Teletyped to move from station to station, so at the

time you thought of the first one—the file computer was used as a computer, and as soon as you

reserved here, then it would Teletype ahead and reserve, and they would Teletype ahead. You’d go all

the way ahead and reserve the space all the way through and print up the tape, the form. Now, you could

call in and change it but at least you could get that far, and so I was kind of the manager of the

equipment, and the problem was that we used Teletype punch and a Teletype reader. Well, the reader

was 60 characters a second.

Hendrie: It was a mechanical reader, right? This is not a photoelectric paper-tape reader.

Thorndyke: I don’t think so. I think at 60 it had to be mechanical, and the punch was 10 characters a

second, and then we started in the loopbox and then we rolled it up out of the loopbox, because it come

in at 60 and that’s too fast for the unit, and then you stored the tape for 30 days for legal reasons, if

something happened. After 30 days you could throw it away, and so then you had 2 things: You read fast

and punched slow or you punched—in other words, on the input you’re reading it and on the output you’re

punching. And so therefore you had that thing...



Hendrie: Now, is it going into the computer too at the same time, or is this just literally tape equipment,

Teletype in, Teletype...

Thorndyke: No. You’re reading the data into the computer as a reservation.

Hendrie: And then...

Thorndyke: And then the computer is all done now. It says—it sends this.

Hendrie: Punches it out. Got it.

Thorndyke: So it punches it fast, and then it slows down and it reads it slow, because teletype is only 10

characters a second, so you punch it fast to get rid of it so you can punch up and down, and we ended up

having—what’d we have? Probably might’ve had 16 stations, so we could handle 16 different Teletype

lines, and so we were young. Christ, what was I? Twenty-seven, thirty-seven, forty-seven? Thirty years

old making decisions that no way in the world later on did anybody with less than twenty years’

experience make them, and so I said, “What happens if we have an illegal message? What do we do with

it?” Sat around and says—we talked for a while. We said, “Hell, let’s send it to the supervisor. Just put

that on the supervisor’s desk, and any message that’s illegal we’ll send to the supervisor.” And, see, in

hindsight that was the most brilliant decision I think that we made for a long time, because the airline area

had a format tape with very rigid fields, so you’d put a character in for altitude. Then there’s five character

for altitude. Then you’d put in heading and there was three characters for heading.

Hendrie: Got it.

Thorndyke: Of every format. A flexible writer read it. You’d read the program tape, stop. You’d add.

Program tape, add. Well, the people in Boston hated the computing system, so what they would do is

they walk along and take the Friden unit and snap it one character. Now you had an illegal message,

because it didn’t have enough characters.

Hendrie: They would take the unit and just...

Thorndyke: They’d take the programmed tape—it was reading the programmed tape and snap it one

character.

Hendrie: Manually.



Thorndyke: So just to screw it up. Well, I’ll tell you, the supervisor got an avalanche of messages. That’s

why I say it’s the most brilliant decision I think we made in a long time.

Hendrie: You’ve got an avalanche of messages and...

Thorndyke: And so therefore they had a problem, and they were continually blaming us for errors and

everything else. We were pointing out that it’s not an error. It’s your people [who] are sabotaging the

system. And so then the other thing I learned was that when you have—and I don’t remember where I

learned this. When you have people that shove their bad unit card reader for a badge reader, that if, in

fact, they are having their badge in a terminal that they’re not qualified to enter—let’s assume that down

in the bay that some coal jockey comes along and starts trying to enter a terminal to say how many shells

were loaded into this aircraft. He doesn’t belong in the terminal, and so what I wanted to do is say that

any time a guy shoves his card in, if his card was not the same color as the terminal that we kept the

card, called for the officer of the day to come down and have that guy explain to the officer of the day why

the hell he’s putting his card in a computer that he shouldn’t be—or a terminal he shouldn’t be putting it

into. Trying to get some discipline, because I learned that from these guys that’re walking by clicking

tapes, and I don’t know if we ever—I tried to get an NT—I don’t know if they ever did, but they should’ve,

that only certain people can enter in certain units. Now, you could handle that also by software. If you

shove the card in and they won’t let you get into the machine, that may be the solution eventually, but

nevertheless...

Hendrie: I like it keeping the card and calling the officer. That’s really cool. “And where’s your card?”

Thorndyke: That’s right. It’s in there.

Hendrie: It’s in there.

Thorndyke: It won’t give it up to you until the guy comes down to open the machine up. Then you got to

explain what’s going on. But, anyway, we had a few of those areas, and so I used to go out a lot in trying

to get machines to work one way or another.

Hendrie: That’s very good.

Thorndyke: But, anyway, then I moved to UNIVAC and we started designing a tape unit, and the problem

that—I’m sorry…

Hendrie: You mean you moved to...



Thorndyke: …CDC. The problem with CDC, they were buying the Ampex tape unit.

Hendrie: I absolutely want to hear this story, but you sometime ago talked about the disc for the drum for

the file computer that you designed up in—now, you said it was very fast or you tried to make it go faster

or...

Thorndyke: Well, yeah, the clock the file computer was a clock track on the drum and so that was a

included [ph?] on the outside of the clock track, and the way you communicate with a file computer, there

are two tracks that were switched and you load one track and then data then you switched to the other

track to load. The computer then would pull in the first track and pull in the second track, and so you

switched tracks to put data in the computer.

Hendrie: Okay.

Thorndyke: Well the problem existed that after you had the file computer, which was a very successful

computer, is it speeded up. Well they decided well let's do a two to one speed up. Not a one and a half;

wasn't enough, so we got to <inaudible> the performance.

Hendrie: Yeah, yeah, marketing wants to make it twice as fast. Or the salespeople.

Thorndyke: that was our—that's the CIRCUS [ph?] didn’t speed up to the one, but we designed the

24,000 RPM drum and at 24,000 RPM we had a hell of a drum.

Hendrie: What diameter drum is it?

Thorndyke: About three and a half inches in diameter is all.

Hendrie: Oh I was going to say because if it's very big you'd fly apart at 24,000 RPM.

Thorndyke: It was a small drum, same size as existing one, and with twice the bit capacity in order to

get it, but twice the frequency. So anyway that was <inaudible>…

Hendrie: And so you built that but it never worked. I mean they never put it in the product.

Thorndyke: Well they couldn't because they couldn't speed the product up, because they couldn't get

the circuit speed up based upon vacuum tubes because vacuum tubes are going as fast as they're going

to go. So anyway went over to CDC and started designing a tape transport patterned after vacuum

capstans.

Hendrie: Which you do.



Thorndyke: Which we already knew how to build and everything else.

Hendrie: You understood all the basics.

Thorndyke: And also the fact of how much torque can you put on a reel of tape before you're in trouble.

And the thing that we didn't like since we're building it for our self—well let me go back a second and say

that the CDC started selling the 1604s, and the 1604 had the AMPEX tape unit on it. I think they called it

a TM2 or the FR300. I think they changed the name as they're doing work on it. The problem with the

AMPEX tape unit was the system had morning sickness. You'd turn the tapes on in the morning and you

had trouble reading and as such you'd to work maybe an hour before you'd get the system stable enough

that you could read and write tapes. And so the customers insisted that CDC provide an IBM controller

so they could buy IBM tape units, which were reliable. Well obviously they lost money because they

didn't get the profit of the peripherals to pay for the software and the controller development. So of

course at that time they were making money so damn fast they could hardly count it. So they decided

that they were going to design a tape unit.

Hendrie: A reliable one.

Thorndyke: Right. And so I applied because I wanted to go over with the guys that were designing it

were the people that did the experiments before. So I went over and my job was electrical interface, the

controller, and the local unit, as well as magnetically. So my job was helping the magnetic design and

that was to be called a 606, and the 606 number because the people just thought it was the most great

thing in the world, so balanced, a six, a zero, and a 6 is just balanced, just a great number. Well I never

told them 606 was the house number of where I grew up.

Hendrie: Oh you're kidding.

Thorndyke: I never told them because otherwise <inaudible> wanted it changed.

Hendrie: And you liked that idea.

Thorndyke: They suggested it I didn't, so I was completely clean.

Hendrie: You were clean, okay.

Thorndyke: But anyway, that 606 came out at 556 bits an inch, vacuum capstan with good start/stop

times and so we built 50 of them.

Hendrie: Now this was designed to read IBM tapes?

Thorndyke: Read IBM tapes.



Hendrie: This was IBM compatible.

Thorndyke: Right.

Hendrie: You weren't trying to do anything strange.

Thorndyke: And you could read 200 bits an inch or 550 bits an inch.

Hendrie: Now was the AMPEX also IBM compatible?

Thorndyke: Yeah. Seven-track head. Then about that time the CDC had an order for a tape system, I

don't know, <inaudible> tape or something to tape, of only 200 bits an inch, not 556, just 200, and so

management decided, Camp [ph?] and guys decided, well let's discount the 200 bit an inch tape so we

get the market because I think there were 50 or 100 tape units involved, that would get us into production,

even though we would bid it lower because only 200 bits an inch couldn't go 556 forever but we could get

the start up costs paid for. So we could now end up almost having a positive cash flow. Not making any

money but at least have a positive or a zero cash flow and so that then got us into production. From the

time we started the tape unit to the time the first one from off the production floor was two years and one

day.

Hendrie: From the time you started development until—wow.

Thorndyke: Two years and one day. And we moved a plant and they built a new plant and after the first

year we moved the plant and then separated and had to start our own documentation and everything else

as well as get this plant to come up to speed.

Hendrie: Okay, but where was this originally?

Thorndyke: It was originally at what we call Cedar Engineering, which was an avionics plant. At CDC

one of the problems with the Navy, as soon as the CDC formed it, they were reluctant to give control to

any contract because they didn’t have any production capability. So CDC went out and bought Cedar

Engineering which had production capability in avionics, but at least production capability which was a

requirement. And so now they could qualify…

Hendrie: They could check the check box.

Thorndyke: Right.

Hendrie: Well we have production capability.

Thorndyke: Yeah, and they used it too. And so we designed our tape unit out there because AMPEX

was so damn unreliable, and the difference is IBM had put in a device called a tape cleaner. What it was



was it looked like the head out of an electric razor where it had all the perforations in it. And so that went

over and the reason that was unreliable is as you wear a tape you have a lot of debris. Well when you

roll that thing up under tension and let it set over night the debris now sticks to the oxide and so when that

oxide comes along and it lifts the tape off the head and you can't read. So until you can get rid of those

nodules, you don't read well. And IBM had this tape cleaner, you run it over that tape cleaner and all the

nodules disappeared and it works. That's why they're so damn reliable.

Hendrie: And their tape cleaner was just built in?

Thorndyke: Yeah. And AMPEX never came to.

Hendrie: Never figured it out?

Thorndyke: Never figured it out. Well we, right away, really early on recognized that that unit and so we

designed in a carbide razorblade type, rather than that thing we had just a carbide razorblade. Well

aftermath of that, or after that was the fact that if you brought us a damaged tape, tape is all wrinkled, we

just sliced the damn thing in half.

Hendrie: Right. That wasn't so good.

Thorndyke: Well, it was because of the damaged tape.

Hendrie: But what if it's a damaged tape and it had valuable information on it. That wasn't so good.

Thorndyke: Well that's tough. You could past it back together but you had to skip that area. So anyway

that then gave us the reliability and then we started producing and the 3600 came along, 3600 computer

which was faster than a 1604 and Seymour was designing a 6600 but that was still later and so the 3600

come out…

Hendrie: Oh the 3600 came between the 1604 and the 6600? Okay.

Thorndyke: Right. And actually the circuits supposedly evolved off of Seymour for the 6600. And he

came to the fact that he could not get the performance out of the circuit and so he scrapped it and

changed technology and I remember reading the monthly reports, he says, "We made a giant step

backwards." And then he went to a transistor circuit.

Hendrie: Rather than a diotransistor [ph?].

Thorndyke: Yeah, and so that became a 6600 <inaudible>. And so the other one was conventional

plug-in cards. So the 3600 then came out aimed at a tape machine and so we sold maybe 30-40 tape

units on it. Because the main thing of a tape unit was a polyphase sort, and if you got this big random

data and you want to sort it—like let's take payroll data. So you got all this payroll data, well you got to



get all the A's in sequence, the B's in sequence, and that sort of stuff, or you got them in sequence of

departments so when you sent the check, you printed out the check and you sent all the right checks to

the right department. And so that required a hell of a polyphase sort. And so the guy come in one day

after we were there and reading IBM tapes to beat hell and one of the marketing guys says, "You know,

we waste a lot of time rewinding, you got to go all the way back to the index to read out and you're all

done." And he says, "And you got to go back and start over again." He says, "Can you read an IBM tape

backwards?" I said, "You're damn right I can." I said, "All I got to do is put in another series of cards that

align the bits behind it you put a master tape and the master tape then takes the head and although the

head may not be perfectly aligned, some of the bits are early or late. So now you get back there and you

put delay on every bit and you…

Hendrie: Yeah, you read the master tape.

Thorndyke: Right.

Hendrie: And you look at it on the scope" <inaudible>.

Thorndyke: <Inaudible>.

Hendrie: Tweaking it.

Thorndyke: By changing the delay line.

Hendrie: Yeah, by hand tweaking it.

Thorndyke: Electronic delay.

Hendrie: It is a delay line. Yeah.

Thorndyke: You're right.

Hendrie: So you would change which delay line you have.

Thorndyke: Well it's actually electronic but it's equivalent of delay but it's electronic delay. And so it

says, yeah, once you get them all lined up now we just read IBM tapes to beat hell. The IBM master

tape's the one we use. Well you read backwards I've got to put another set of delays in because I'm

reading it backwards. What was late before is now early. And so we started reading IBM tapes

backwards and oh, Jesus, IBM guys were just all over us saying, "What in the hell you doing?" "Well we

can read your tape backwards." He said, "IBM can't even read our tapes backwards." So that was a hell

of a marketing because now you can sort by reading backwards and all you had to do then is go in the

computer memory and then vert [ph?] the block, take the block and turn it around and you got it in the

right direction. And that's a lot faster than…



Hendrie: Just rewinding and starting reading again.

Thorndyke: Then by the time we got introduced to 556, IBM introduced 800 and so we ended up then

designing a 9-track head for 800 bits an inch and I had a guy by the name of Wally Edwards that was

very, very gifted and to some extent kind of a prima donna but not in a bad sense, and he would

terminate. Once a program was done he'd be out looking because he didn't know what was next. I

rehired him five times. He was that damned good. So I'd go out and he'd leave and they'd stay in about

a year I'd go out and tell him about time he come back to Minnesota, and he used to call me Hoss. I don't

know why but <inaudible> Hoss and I remember one time he called me up and he was gone for a week.

He says, "Hoss, have you filled that job yet?" And I says, "No." He says, "Can you mail me an

application?" And I said, "Well, Wally, what we'll do is we'll just call that a leave of absence. Get the hell

back here." So anyway Wally, after he got this 800 bits an inch going, come waltzing in, he says, "come

over and let me show you something." So he would take a tape, write it, turn around, start reading it, and

when we had errors he'd throw the errors over in a box and then he'd read those errors. Any time he'd

<inaudible> throw that over in a box and about the third iteration we had a pattern that the tape head itself

could not accept. It would read with errors. So all the sudden he proved that I can write permanent error

tapes that he could not read with his own unit.

Hendrie: Can't read something it's written?

Thorndyke: Right.

Hendrie: Oh my goodness. Okay.

Thorndyke: Oh Lord.

Hendrie: Oh Lord, what's going on here?

Thorndyke: All hell broke loose. And what happened is that you got a gap in the magnetic head where

the—well as you come to the edge of the core it operates like an infinity gap. So as this bit goes

underneath that back edge now, in fact, you've got an infinite gap and that ends up having a small blip

and so now all the sudden you've got a <inaudible> but you've got a little spike in it and as such that

needed to be <inaudible>. So it's a rate of change and a square and a high rate of change <inaudible>

little radius is a lower rate of change. And what it was is the bit pattern was <inaudible> a magnetic

amplifier almost because a bit pattern together had to have a certain characteristic in order for that to be

important. So Jesus.

Hendrie: And he just found experimentally.

Thorndyke: He found it by using a garbage dump, he called it, any time he got an error in a tape he put

it in the garbage dump and that resolved it and…



Hendrie: So eventually you were able to figure it out?

Thorndyke: The solution was to increase the gain of the head. That's the thickness of the gap and so

we wore the head half down so we reduced the thickness of the head so that there was a lot more gain in

the original signal so this blip was much, much less. So it's a distortion so when the pulse was not very

high he has a big distortion and the heat detectors would detect it. However, when you had a big pulse,

this heat detector wouldn't detect it.

Hendrie: So you literally increased the gain in the head?

Thorndyke: Right. The magnetic sensitivity of the head.

Hendrie: So you actually had to change the magnetic of the head.

Thorndyke: Right. Yeah, and so it's more sensitive but this edge didn't change, it's still there, but it's just

a ripple now. So anyway yeah, so Wally really his value was the fact that he designed our controllers

mathematically. No blocks. He wrote equations. So he would write the entire design of a controller with

equations.

Hendrie: You know the west coast pioneered designing with equations and it was an east coast thing to

use logic diagrams with blocks.

Thorndyke: Yeah, no, well that's <inaudible>. We <inaudible> as <inaudible>. The stuff they built was

so <inaudible>. But yeah this was back in what, about '64, '65 and I had him at UNIVAC, at UNIVAC he

worked for me and then left and hired him back. Control Data had a salesman that was very acquainted

with a few of the Control Data people that come over and says he wanted to be a sales person for Control

Data and they looked at him and says, "Well, all you sold is mechanical hardware.

<off topic conversation>

Thorndyke: Harold Brooks was a salesman that came to CDC and says he wanted to sell computers.

They said, "Well it takes a graduate of electrical engineer to sell computers." He says, "No, I don't want to

sell computers, I'd like to have the privilege of being <inaudible> personal representative to a customer

that has not selected a CDC unit." He says, "I want to go out and talk to those type of guys." They said,

well, okay," and he says, "Okay, so what I want to do is go out and visit customers after CDC lost the

order. And I can go down there with Mr. Norris' blessing and speak for him and find out what it would

take to get the order." So he went down to a customer that had about $12-14 million worth of computer

that CDC placed very well in the runoff in a test but not so well in price or something else. So he goes in

and tells the customer, says, well, how did the <inaudible>? Oh great. You want the machine. Yeah.

What was the problem? Well it was too high. What will you pay? What do you think is a fair price? What

would you be willing to pay? He said, thank you, and he goes back to Norris [ph?] and says, you can get

the order for this machine for this amount of money and so then you start looking in and says, well, in this



case, toward the end of the year, and you got a machine in inventory that's worth a lot of money, and do

you peddle it or not. The answer is yes. So you peddle it at the price that the salesmen would never be

allowed to sell it for but this was sold as a <inaudible> of Mr. Norris to keep a good customer and that sort

of stuff. And the entire marketing crew were benefited is this, they have sold a machine. So their

commission, salesman on the account was commissioned as if he'd sold it, so he didn't have any

animosity…

Hendrie: That's important.

Thorndyke: Had a lot of cooperation, everybody was happier then <inaudible> got the order and so then

he come out to me and says, I'd like to sell your equipment and so I said fine. So we made sales calls

together and I was describing one of the sales calls that we went to a medical company that had a

contract to deliver a computing system that had 50 IBM tape transports.

Hendrie: Oh this was Beckman?

Thorndyke: This was Beckman.

Hendrie: Yeah.

Thorndyke: And that the IBM unit was selling for around $45 to $50,000 I remember in that general

range and so we went out and I was…

<off topic conversation>

So Hal then said, okay, on my first sales call with him we met with the couple of engineers I brought along

and I was general manager of the division then and he says, okay, we're going to meet for breakfast at

this time, he gets in there and he says, okay, here's our strategy, he says there's nothing new. I don't

want to hear anything about the future. I don't want to hear anything that's better than this. All I want to

do is talk about this tape transport only. And he says, if I started <inaudible> get off the damn subject. I

don't want you to talk about it. This guys' already sold. We don't have to sell anymore. And this is

Beckman because they allowed us in and he says, and if you're doing well I'm going to scratch my ear or

something, he definitely didn't want him to hear, and he says, then I'm going to pass the ball to you, the

other guy and all of you <inaudible> cover these subjects and then you hand it to Lloyd. And he says, Oh

by the way engineer, can your boss sign this order? No. Well can his boss sign it? No. Well who can

sign it? Mr. So and so is a person that can sign the order. Oh Mr. So and So, <inaudible>. No but he's

up in the upper floor. So he excused himself, and we're going along with the engineer in trying to

<inaudible> how it'd be nice to have our unit. "Oh no, I don't want to design the controller. It would take

too long a time and this and that and everything else." So Hal comes back in the room and right after

about 10 minutes he <inaudible> we got this other meeting we've got to go. we could come back or we

will come back next week if you're interested and the guy says, no, no. So we get outside and I said, we

didn't make any progress. He didn't want to design the controller. Not a chance. He's, "I got the order."

I said, "Hal they haven't even decided yet." He said, "I got the order." It says <inaudible> I just pointed



out that our <inaudible> which is IBM compatible right? Yeah, we read and write their tapes. We’re

compatible at half the price that IBM will charge. Now he built a fixed price contract. The fact that he can

save a million, a quarter million and a half dollars on the contract gives him a hell of a lot of room to do

things. And he understood it. In fact, <inaudible> IBM compatible. That means on the taped document,

not the interface, just the tape document. Wow. And so I learned a lot from him and his gestures I've

always used with our guys. If I start doing this get the hell off the subject. I don't want that talked about.

And I made a lot of sales calls with salesmen, I used to be the sales support for most of our products in

the peripheral area, both because the engineers needed to be home to get the job done, but number two,

I wanted to meet the customers to find out what they thought next. There's that planning, where's the

market going, what should be doing? So I used it as a planning area, but he taught me a lot but he was

very inpatient. He just demanded that it's got to be done right now this way and that way and I was

remarking that his son bought a motorcycle and he was out there kicking and trying to get it started and

couldn't get it started and Hal come out and says, "Well, tie a rope around the bumper hitch and put the

rope around the handlebar and we'll tow it to get it started." The kid said, "Gee Dad, that's kind of risky."

"Well, hell, you drive it, I'll do it then." And so he was standing there playing, he got the throttle wide

open, he started playing with a high speed jet needle valve it all the sudden takes off and he's accelerated

to beat hell up alongside the car. The kid looks out, sees the old man passing and he jumps on the

brakes, laid that cycle down and skinned the old man down the road and he come in with a lot of road

burn and the damn kid should've been smart enough to speed up and that was his attitude with

everything. He finally killed himself because he didn't obey the rules of aviation very well. He tried to

overpower them like he did everything else, but it was a great loss for us.

Hendrie: Okay. That's a good story.

Thorndyke: So anyway, we learned a lot from him and I was almost taken up flying then and when he

killed himself in an airplane I decided the kids were too young and I gave up. Never did take it back up.

But anyway the tape transport was our high volume product and we were making very good change on it,

it was very, very good. I used to say that in the tape units we needed about 5 times our cost to

manufacture without the corporate stuff in R&D since R&D was expensed, we needed just the material

labor and burden, we needed about five times cost. IBM was always held up as the error [ph?] because

they got 7 times cost. IBM guys come in and say, "Oh IBM produces for 1/7." Well they had a hell of a lot

more volume then we did. But we didn't feel that our cost were all that bad so you sell the tape unit for

$45,000, and you produce it for about $9,000. There's a lot of zeros in that profit. We're selling 200 a

month. There's a lot of zeros.

Hendrie: Yes, exactly. That's very good.

Thorndyke: Before you get to the significant digits there's a lot of zeros. So as such Seymour we’ll get

into him, but people when they edit they can put it in the proper place the 6600 when it was introduced

had a mean time between failure of about nine hours. That's hardware and software. And the people

were buying it because it was so hellaciously fast when it worked. So as such their arguments are in one

of the cases, one of the labs says, "Well yeah the IBM machine runs around 50 hours, and you guys are



doing it in less than 9." That's a significant difference, and so run it twice. What the hell, we're still ahead

of the game. That went on for awhile.

Hendrie: Well they worked on the machine. Did they figure out what the problems were that gave it such

a…

Thorndyke: Oh yeah, it was hardware and software.

Hendrie: Was both hardware and software?

Thorndyke: Right. It's a brand new machine. See they bought the first machine.

Hendrie: Okay so there wasn't a lot of experience.

Thorndyke: Fernbach—come in and he wanted the first machine because it was so damn much better.

Hendrie: Is this the prototype?

Thorndyke: Well it was his hand-built machine, right.

Hendrie: Then there wasn't one before that?

Thorndyke: No.

Hendrie: Oh my goodness. So he really got the first one.

Thorndyke: Right. Bought the first one and then he bought the second, and then they kept buying them

and so Sid Fernbach put up a specification he had to meet and if you met it they bought the machine and

help you do the software. So then after about a year some smart programmer come up and says, well

why don't we do a dump every hour. Let's dump the memory into the unit so if something goes wrong we

only have to back up a maximum of an hour. You don't have to back up the whole time. So we can do a

check point restart. So now they come and it says the half-inch tape is pretty slow, you got anything you

can do? And I said, well yeah, we can put a dual head on. We can put a one-inch tape instead of a half-

inch. We got all the capability of one-inch tape so I'll put a one-inch tape, we'll build the head twice as

long, and face off the loop box and everything else the same. And we did that in about 45 days and

Arden Hills only had to enlarge the controller to handle a 12 bit word instead of a 6 bit word. And a 12 bit

word happened to be the PPU [Peripheral Processing Unit] of that 6600 so nothing changed there. and

so now they got a tape unit that would dump in half the time and that became the 626.

Hendrie: You just designed it in response to a problem.

Thorndyke: Right. So then marketing come in and says, you know, now you got that one-inch tape unit,

he says, if we could read seismic tapes, we could sell the oil industry a computing for simulation and for



seismic work. And I said, well what is it, well it's a one-inch tape. I said, what's a head, and he says, well

it's what is it, it’s a one-inch tape. I says what’s the head, and he says it <inaudible> 21-track tape. I says,

can you get a head spec. So he got a head spec, so we sat down and looked at it, and says, yeah, hell

we can build that head. So we changed that, built that head, and then put in the extra electronics but it

would simply take an existing electronics and more of them.

Hendrie: And it ran on a one-inch tape too?

Thorndyke: One-inch tape. The one-inch tape was already in existence.

Hendrie: Yeah. Now did you have to get people to make one inch tape for you?

Thorndyke: Well one-inch tape was standard.

Hendrie: It was the standard?

Thorndyke: Yeah. And so we did that job in about 45 days and CDC dominated the seismic

performance. We sold computers all over to the seismic people because it's hellaciously fast. The

difference of the scientific computer is big blocks of data, an awful lot of data rate. The IBM is small

blocks, multiple blocks of small block like your personnel record, your paycheck record, <inaudible>

supply a mess of small blocks, a lot of them. We got one problem and it's maybe 10 to the 12 bytes. A

trillion bytes worth of data that we're streaming in.

Hendrie: Yeah, so you need to be reliable and fast, and they do not need incredible start-stop times to

jiggle between blocks.

Thorndyke: Right, and so it's data rate, and then after we built that, Bell Labs come along, and says that

you guys are great, and that. We'd like a tape in it that could transfer at 10 million bits a second. Well IBM

was almost a million bits a second, so they wanted an order of magnitude more data rate.

Hendrie: Why?

Thorndyke: Because they were designing a computer that would do ICBM intercepts. In other words, the

Star Wars, back then they were doing—and the—so we said, well, two-inch tape, you know, we can

buy—if we go up to two-inch tape, we could end up building a head, that had 36 tracks. The standard

nine -rack IBM head, let's make four heads in that block, and then, because of what they want, let's take a

density from 800 to 2,700 bits an inch, and read in a 32 bit word, and a function channel and a parity

channel and leave the outside two area tape, which is the most unreliable, unused. So we ended up with

a—and the reason for the function channel is, I wanted to put in non-tape data. For instance, start of

block, end of block, on a function channel, because they wanted to do continuous recording, so what we



did is, we backed up and then come ahead, and when we read the end of block, we started recording the

new data. And so what they were doing is, on a missile shot, they were acquiring all of the radar data and

storing it on tape, with real time data, as long as they got it, and then they take this tape, and use a

simulation tape, and then they run it by and see the intercepts, and just continually running this by as if it

were the missile shot, just continuous with the real time data in there to slow it down. And they bought a

mess of them, and they—so we bought a one inch—or a two inch tape, or a one inch tape, I'm sorry,

modified a two inch tape, and then sold them all the stuff we took off, so that they could not get it on a

CPF contract, cost plus fixed fee. And so we sold them as a standard product, and we cost them for

disassemble, put them in a box, shipped the parts to them. In the meantime, then, we modified it to two

inches, and then we had to produce an egg crate [ph?] buffer, in order to take the 32 bits and line them all

back up again at that density. And so we bought a memory out of the 3300 computer, and then, that's a

shift register memory, and shipped the whole thing, and collected 250,000 dollars apiece, and I think we

made ten or more of them.

Hendrie: There's nothing wrong with that.

Thorndyke: And then, well it was about four years later, they come back, they had worn the head out,

and wanted us to rebuild new heads, so we built them new heads and sent them back to them again.

Hendrie: Oh my goodness.

Thorndyke: But that was a tape evolution.

Hendrie: And how did you get the increased density, though? How did you go from 800 to 2,700 bits?

Thorndyke: Because we could get away from IBM compatibility.

Hendrie: Ah, okay.

Thorndyke: And so now we just ended up just packing the density an awful lot tighter, and there was still

a lot of capability. A lot of people are recording at that density, that was not the issue.

Hendrie: That was not a big deal, to record at that.

Thorndyke: No.



Hendrie: But did you have to use a different kind of recording scheme?

Thorndyke: We used Manchester recording.

Hendrie: Okay, is that what the 800 bits per inch—

Thorndyke: No, the 800 was—

Hendrie: Just a regular NRZ?

Thorndyke: A single flux change. It went from a zero to a one, that's a big. From one to zero is also a bit.

And so effectively, you're still reading all of those in parallel, and this, each channel was read

independently. So we're reading each—and then you've got all these bits coming out, and then the egg

crate buffer starts shifting around to line everything up. And—but it could put in function channel, you put

real time stuff in, interrupts, you could also throw interrupts there, as where the computer would be

interrupted if you wanted that. So it was a—They wanted—

Hendrie: Very flexible.

Thorndyke: They were in love with it. But that was about the end of the tapes, and so after we got the—

we started doing this disk for Seymour, and we got into it about a year and a half, and CDC introduced

the 3000 series computer, which is kind of a competitor of IBM in the business area, and IBM announced

that they had a 1301 disk drive that had a replaceable pack. And my engineering budget that year was a

million dollars.

Hendrie: Oh yes, now you went through this, about how you went and got—bought the disk, okay.

Thorndyke: Yeah, let's forget all—so—

Hendrie: Yeah, let's skip ahead now.

Thorndyke: That happened and then—

Hendrie: So then what happened?



Thorndyke: So we then got it in, and I was going to simply do with part of the unit, and Mr. Perkins

decided that the Seymour program was so critical that it couldn't be delayed any way, shape or form,

because Seymour had purchased a Bryant File. Now a Bryant File was a big file with a big heavy

hydraulic actuator.

Hendrie: I've seen one, I know that file. We used to buy drums from Bryant, so I know Bryant.

Thorndyke: Okay, and so the thing was ________ that a proper programmer could start hitting that by

request for head movement, and walk the damn thing across the floor.

Hendrie: Wow.

Thorndyke: Because of the impulse. And so that's why we went down the road, said that we had to have

no impulse into the floor, and so we chewed around and chewed around, and—

Hendrie: Now this was for what machine?

Thorndyke: This was for the 6600.

Hendrie: This was for the 6600—

Thorndyke: To replace the Bryant File.

Hendrie: To replace a Bryant—now you're doing this before you had to do the tape, because the 6600,

obviously isn't done yet, when you're doing this.

Thorndyke: Well the tape was for the early 6600, and then we had started the disk in parallel, and so—

Hendrie: And so then they started with the Bryant, so now the Bryant isn't working—

Thorndyke: See, we started the program a year and a half before the Bryant File came about.

Hendrie: Got it.



Thorndyke: And so we then started the file, to try to understand how to build it, and all the interesting

piece was that Dan Sullivan [ph?] and I both, when they were hunting for the guy to run the disk program,

we're having—I was having too much fun with tapes, you know, and traveling and enjoying the life, and so

therefore they got serious, and Perkins said, "Well, Dan, you and Lloyd don't want to do disk, you've done

them, so we've got to go out and see if we can hire some people." And I said, "Well, what's the budget?"

He says, "A million dollars this year." I said, "You're going to end up giving a million dollar program to

guys that never designed a damned disk in their life? Hell, I'll take the job." I said, "If you're going to waste

that much money, why, it's time for me to take the job." And so Sullivan and I went along. And the—so we

started the design about, probably a year and a half before Seymour got the 6600 running properly. And,

as we started looking at it, because of the crudeness of the technology at that time, or the infancy of the

technology, said that you had to use a large amount of disk area to get the density. We were at 50 tracks

an inch, and probably about 1,000 bits an inch, in that range, and so we needed a five-inch recording

band, which made a 26-inch diameter disk. And so we stacked 64 up, and then a part of that, it says, well

you know, if we had two spindles, and had a positioner push two masses in and out, we could counteract

it. Now that came out of Jack Rabinow. Jack Rabinow ended up sometime, I think, after the war, it could

have been before the end of the war, did a job for the navy that says, one of the problems with fire control

radar is, it dithers. It sits there, and it just dithers back and forth. And the dithering rate determines the

accuracy. Well, as soon as you take that big mass and dither it, now you've got the whole structure

ringing. You've got a big ring, and you've got a vibration going back and forth, and so therefore, you and

so what he did, is took equal mass, and shoved the two masses apart. Now there's no impact into the

structure. So he had two hydraulic positioners, just push them back and forth—

Hendrie: Okay, and one was just a dummy mass, and the other was the radar dish.

Thorndyke: Right. And so you could end up—we saw that, and says, hell, let's put the two spindles in,

with identical units and push them back and forth, and put synchronizing bands, so they move together,

and that becomes the 808 disk file. And it was—had no impulse into the mass. As I said, you could just

stand there and hammer it to beat hell, and end up with no impulse. And you could stand a nickel on it all

day long, and—but it took us a long time to understand how everything had to be on the center of mass,

or on a cantilever up on it. And, because we needed to get a 12 track reading in parallel, we ended up

having to have the heads interlaced with tracks in between, because the head was too big, and so we

had a major position—

Hendrie: So you couldn't get—the tracks, you could record on the track spacing closer than you could

build two gaps close to each other.

Thorndyke: Right, and so what we did was, we made a major move and then an incremental minor move

on each side of it. So we did the major, and then you increment to the other side of it, which was about a

ten thousandth shift. And so that one track then covered three. One—so every third track was a new

head. And so—and then we read all 12 bits in parallel. So we read 12 bits in parallel out, which now



matched the PPU speed of 6600. So now I've got a supercomputer that is reading 10 million bits a

second.

Hendrie: Wow. That's pretty darn good.

Thorndyke: And that's a—Well—

Hendrie: Is the data inter—but the data is all on just one of the disks.

Thorndyke: No, the data is—

Hendrie: How is a given word—I'm a programmer, I want to go get a low block of data. Where—is it split

between the two disks, or not?

Thorndyke: In CDC's area, we sectored the disk, and so you didn't have the IBM count key, where you

had to read the index. We ended up with—

Hendrie: Sector disks, just like drums were.

Thorndyke: Sectors. So you just had to find out the sector you want, and you go look for it.

Hendrie: Yeah, it's just like drums were always sectored.

Thorndyke: Right. And then, in fact, even later on, the program got sophisticated enough, after you read

the sector, they'd look ahead, and says, well within this distance, we can move and catch this new sector,

even though it's not the one we want. So we'll retrieve it out of order, and let the system put them back in

order. So you could start moving around and picking up sectors during a revolution. This was assuming

you had to wait for a full revolution.

Hendrie: Yeah, I understand.

Thorndyke: And so now we started moving all the time. I ended up taking counters and sticking it on the

2311 we had, that IBM disk pack on a computer, on the 3300, and then I did the same thing on the 6600.

I found that we were making about 250 disk moves an hour, seeks an hour on our 3300, the way they



were using it, so now we go over to the 6600, I was counting up as many as, almost 20,000 moves an

hour.

Hendrie: Wow.

Thorndyke: As they were jumping around. Now that was when they were after sector bases, rather than

big avalanches of data, and that's why the 6600 performed so damn well. There's not a supercomputer

that was designed that ever succeeded without a CDC disk. None of them—they, none of them

understood the I/O rate need. Now the—back to the small disk for a second. One of the problems that the

small disk, when they first started putting them on the 3300 computer, the disk, on the 3300 computer,

ran slower than a tape unit. I said, wait a minute, the program runs longer on a disk than a tape unit. Well,

in the tape unit, you have access to record and in three milliseconds, you're in the next record. And so

they took the disk, and treated it as an incremental tape unit. They laid the disk down with the

incremental—with the tape in a series.

Hendrie: You're kidding.

Thorndyke: No, so therefore, instead of randomizing it, they ended up as a—you had to move and mess

around. They didn't—they couldn't sequence it. And it wasn't until they started putting the records down in

a random basis, that you started taking advantage of the seek time of a disk.

Hendrie: Yeah. Oh wow, so they were just using it as a—

Thorndyke: Because it's a sequence, once if I—if I miss this record, I have to wait for a full revolution to

come back again. Now I've got 1800 RPMs, so I've got 30 milliseconds or more. The next record in the

tape unit is only three milliseconds.

Hendrie: I was going to say, the tape is moving, the tape is going faster, yeah.

Thorndyke: So instead of laying it down, and optimizing it for randomness, and once they did that, then

tapes became shelf store. And you didn't shelf store a disk, you shelf stored the tape. So anyway, that

was the—but the 6630—

Hendrie: Can I just go back for just a second, because I've got a question that's nagging me. You said

something about, on the one for the 6600, that you synchronized the two disks. Does that mean you

synchronized the rotation of the disks, or—



Thorndyke: Yeah, why we did that, is—

Hendrie: And why?

Thorndyke: Well, by accident. This had a motor in the center of the shaft up, and the shaft down. The

shaft up and the shaft down. These two disks here, with different actuators, are synchronized. Okay, what

we did then, what they did—

Hendrie: Yeah, because they're on the same shaft.

Thorndyke: Yeah, and so the area was, you streamed out of the upper disk, into the computer, and back

onto the lower disk, so you didn't have overrunning buffers.

Hendrie: Oh, well that's pretty clever.

Thorndyke: Once they set it up, they didn't—and we didn't—that was not intentions, but once they found

out that, mechanically, now you've got it in the data rate, you can't have overrunning buffers. And all you

had to do was have enough storage for a revolution, because once you do it, now you're—and so you

empty it, and you stream in one of them, and you ping pong it. Livermore was great for ping ponging, take

the whole damn thing, flush it through the computer, wiggle a few bits upper, come back, wiggle a few bits

for the lower. And so you ping ponged it. And of course they were talking about, you know, ten to the

eleventh, ten to the twelfth, bytes of data, and so you wiggle a few as a differential equations, and as

such, you just had to flush all that data through.

Hendrie: Yeah, okay, makes a lot of sense.

Thorndyke: So they just made it come back and forth. Now I—the other day, oh, this is—not the other

day, probably six, eight years ago. They were talking about the speed of the current computers. Can, in

fact, you go to archives and pull out a design and review it, and the answer is no. You can't go get a

design that you have archived, 10, 12, 15 years ago. By the time you get it, put it on, come in at a low

speed, right now, if you have the program that created it, you can run the program under the high

performance computers faster than you'll get the old information, re-compute the whole damn thing. You

can re-compute it faster-

Hendrie: Than you can get to the archive storage.



Thorndyke: Than you can retrieve it.

Hendrie: Wow.

Thorndyke: And so that's a kind of a change. I don't know how far that's gone, because that was, oh,

hell, I say a few years ago, that was about 20 years ago. Their comments are now, that a lot of times you

can't retrieve the data, you can re-compute it.

Hendrie: Yeah, isn't that—that's pretty interesting.

Thorndyke: So anyway, we then did the disk, and IBM announced a pack that, I can't remember the

name anymore, but it was a ten high pack, rather than a five high pack. And so as such, a marketing guy

comes, oh, we've got to have it, you know, if we don't have it, the next four months—

Hendrie: The world will end.

Thorndyke: The world will end. And so you announce everything, and so I had the guys sitting around,

and said, Jesus, you'd think these are in drawers or need drawers, and it's a big system. Our engineer

looked at it and says, "You know, that design is going to be a real son of a bitch." And that became

RESOB, and RESOB caught on in the industry. RESOB was an industry standard name. And so we had

to sanitize it so it becomes Reliably Engineered Stacks Of Bytes. So we salvaged that. But we did it, but it

was not really a product for CDC, it was a product for some other people, and then, about that time,

CDC—

Hendrie: Now were you—how did you, you know, when you did the 1301, something to read the 1301

disk pack, did you—and you had an IBM unit, so you knew what they did. What sort of innovation—you

know, how did you—you needed to make it cheaper than what IBM—that isn't too hard, at seven times.

Thorndyke: That's blinking now.

Hendrie: Yes, it is. We have five minutes.

Thorndyke: Okay, so the area that, once we got it in, I was not allowed to do it. It was given to a brand

new crew, that never designed a disk before. And so they decided they were going to put an electric

motor drive on a rack and pinion, and use a detent on the gear drive. And well they were sophomores,



and they—then after a while, we formed a disk division, of which I was appointed the general manager,

and I picked up that 854, and it had 5500 change orders for the first 3500 production units.

Hendrie: Sophomore engineers. That will do it.

Thorndyke: Sophomore engineering. And so—and but we were selling 600 a month.

Hendrie: But it was still successful, and it worked.

Thorndyke: Right, 600 a month. And we sold it OEM, to the point that, after we had it, the rest of the

people came through that they had to have a disk to compete with IBM, and Excello was proposing that

they would do a disk for three million dollars. So they come to CDC, it was already in production, so

Control Data sold to them without any engineering costs, other than the cost to tailor to their site. Like,

they wanted their own instrument panel, so that they wanted—

Hendrie: They want their own colors. I mean, there are a million things everybody always wants.

Thorndyke: And their own connector, which is nice for us, because once it's their own connector, then, in

fact, we couldn't sell it to anybody else. So no one could come in and buy a Burroughs machine, if

Burroughs were the customer, say, because now you're selling proprietary I/O design, and so we wouldn't

do it. And since they had to put their own connector on it, they couldn't plug CDC.

Hendrie: Right, so they couldn't come back at you and use it in a CDC.

Thorndyke: Oh, marketing was bent out of shape. He says, oh, they'll plug us. They can't plug you,

because they can't get the CDC connector for the interface. They have to define the interface to us. And

so we could sell it at below cost. Robinson-Patman Act was something we were very alert to, and

Robinson-Patman says that you can't discriminate against people and price it in such a way that you

encourage one and not the other. And so what we did in that, is that, since they did all the distribution of

the manuals, the training, and buying the spares and everything else, we could sell them at a lower price

than CDC, which had to have all the spares and the training, and they were selling everything internally.

So we could sell it at a lower price, and justify it.

Hendrie: Yeah, okay. Good.

Thorndyke: Shall we—



Hendrie: Yeah, do you have a little bit more on that, or—

Thorndyke: Oh, I don't know the—but anyway, the—Then I took over the division, and we got that unit

stabilized, and then about that time, the—Norris [ph?] instituted the lawsuit—

Hendrie: Okay, can we—

Thorndyke: Yeah.

Hendrie: All right.

Thorndyke: Yeah, with the—in 1971, I was over in research, doing research on advanced peripherals of

one type or another. We did a product called Quadrasab, [ph?] and the thought was, we spend a lot of

time in the data center, turning a disk drive down, swapping the disk out, putting a new one in, and turning

it back on again. We had a four spindle device, where you could end up replacing a single disk, and then

have the actuator move around to one of the four drives that's continuously move it back and forth. You

could have an awful lot of higher throughput, and as such, you'd also have four times the amount of

storage online, and it would only take you about a half second to move from one disk to the other.

Hendrie: And you could take any one offline.

Thorndyke: Anyone offline and change the disk.

Hendrie: Change the disk, while the other three are operating.

Thorndyke: If you had a job that said it required three disks, effectively get the three disks online, and

you had waste—you've limited a lot of waste time, so we built that device, and then it was the rest of the

technical people at Normandale, took the position that, oh well that wouldn't work, and you're going to

have too many head landings. We landed the heads a million times, and CDC had a proprietary head that

no one understood, and most of—IBM used a centered slider. Well, a centered slider, no matter how the

hell you do it, it's got micro-cracks. Now micro-cracks, as they touch the disk, scarf up the oxide, and

eventually crash. We ended up having a full saran glass. Now the full saran glass is a glass that is

etchable until you cure it. And so you can take full saran glass etch holes in it and everything else you

want, and once you end up heating it, now, in fact, it's—becomes a piece of glass. So what we did is, we

etched the slot and the other things we wanted in that slider, put in a head, a magnetic head, and put in

glass around it, centered the whole thing, so now we had a complete glass and head slider that didn't

have micro-cracks. And one of the problems of that, everybody had, is when you take a slider and epoxy



and a ceramic, you've got a differential expansion of different things, and especially the plastic, the epoxy,

and if you didn't really do a tremendous job of heat treating the epoxy, you'd find micro-shifts. And the

way you did that, you had to go over to the government, and run through a temperature cycle of minus

63, and 363, and 300, for 24 hours a day, you were cycling it. And of course as you cycled to 300, now, in

fact, you were staying up to—you were curing it more. The rule of thumb is, the fact that, with chemical

reactions, you double—every ten degrees centigrade, you double or half the reaction time. You're

probably aware of that. So if you say epoxy takes 12 hours to cure at room temperature, 30 degrees is six

hours, 40 degrees is three hours, 50 degrees, an hour and a half. And by running through the

temperature cycle, where you run it way up, you get the last of the curing done, and so you can stabilize it

pretty well, but you've got to go through that cycle. And so it's essentially then, the slider, we could start-

stop, we didn't have to retract heads. You let it coast down and you go back, but the guys were against it.

Some of the support group was against—so we dropped it, and then we started working on a 22-inch

wide tape unit. And it's called Scroll, and we buried the heads in a drum, and then moved the web back

and forth across the drum.

Hendrie: Oh, all right.

Thorndyke: And it was an engineering marvel, and we used a 96 foot roll of tape, and every eight feet

was a new disk pack, and so effectively, then, we just put disk packs all over it, so you had 1,000 disk

packs online. And but it was shut down, because we couldn't solve the inner division competition. About

that time, we had a guy come to us from IBM, that Tom Camp [ph?] hired, name's Bill Morgan. He came

in with the promise that he had brought with him IBM's secrets. And as such, he was one of the inventors

of the data cell. And so he presented patents with his name and the data cell. One of my engineers went

to the patent and pulled the patents out, and find his name was not on the data cell.

Hendrie: Oh my God.

Thorndyke: Well he's that type of guy. In the meantime, as we were learning to code disks, he was going

around and intercepting all the data and compiling it, and selling it in Europe, to people who wanted to

start machining disks.

Hendrie: You're kidding.

Thorndyke: No. But part of that was, he brought along this memory module, which IBM was doing, for the

3340, where you'd take the pack off, and the actuator and everything with it. And so in about, probably

August of I think it's '71, Normandale started losing—the peripheral people started losing their butt big

time, because what happened is the general manager who was a manufacturing guy, had so much OEM

business, he stopped all new product development and just put them on customers buying the existing

devices. Well, what happened, he missed the next evolution, because he wouldn't fund it, and now they



had a tremendous spiral down. And so Norris called me out of research, and said, you've got to go over.

And I said, well, you know, I have a problem. I've made it known that I would not work for the SOB, and

he's going to be over there, and I said, I'm not going to work for him. I says, I'll quit before I have to work

for him, because he is not interested in engineering. So I got called over to Norris one day, and I told the

wife, I may be out of a job. And he started talking about it, and I said, you know, I have a trouble. He says,

"Yeah, I know about that." He says, "He's now been removed. He now works on my staff. Now get the hell

over there and straighten it out." So anyway, part of that memory module came over, and he was insistent

that's what we had to develop, an IBM compatible pack where you moved the actuator and everything

else. That is not a shelf store device, it's too damned expensive to be shelf store.

Hendrie: Yeah, now this is this new general manager.

Thorndyke: This is IBM—no, that general manager was removed, and then I went back in to head of

engineering, with my 30 people, against his 330.

Hendrie: Who's the his?

Thorndyke: The name of Steve Popovich. Now Steve Popovich was general manager of the engineering,

but Steve was—

Hendrie: Of all engineering, or—

Thorndyke: Of all peripheral engineering in Minneapolis.

Hendrie: And you were just in charge of engineering—just taking a new job.

Thorndyke: Well, that's what—I replaced him as chief engineer.

Hendrie: Oh, you replaced him, got it, okay.

Thorndyke: I replaced him as chief engineer.

Hendrie: I was just trying to understand who was who.



Thorndyke: The problems were that he was not suited to be general manager. He ended up cutting

corners and everything else; doing things that were out [ph?] like having parts delivered to his house and

then bringing them in and then expecting marketing to pay it. Well there’s no purchase order, and so all

of a sudden it just—it’s just not right, but anyway, so I said oh they’re losing their butt and we got rid of

that guy and we started assessing it and we missed a generation; we missed a generation of products,

but yet the technology was there and so in the matter of about three months I killed the IBM memory

module and listened to our argument is what we need is a—IBM brought out the 3330 which is a very

high density recording and so the problems are, that was a 300 megabyte pack. Well, our customers

were down in the 30 - 60 megabytes.

Hendrie: Yes.

Thorndyke: And essentially, what the hell you going to do for them? That was our big market in that

emerging market and this IBM device was very expensive, with a shelf store even worse and Tom

Dougdale, one of the engineers and marketers said well what we got to do is to build a 3040 megabyte

drive. We says well what happens if we take the 3330 disk and build a small pack, maybe a 3 or 4 disk

pack so this 8 or 10 disks, there’s 20 megabytes a disk; let’s put on say 3 disks with a cover disk, and

make a miniature 3330 and then ___________ turn of that 3000 RPM. He says, no, no, no, you can't do

that, you turn the 3600 RPM, that's the standard; everybody else has the 3340 that IBM brought out as a

3000 RPM. We’d found years ago in to ___________ at IBM you had to ask—you had to offer 30 percent

more capability or 30 percent less price. Take your 30 percent either way. Well I’d rather take the 30

percent more than 30 percent less money.

Hendrie: Yes.

Thorndyke: Okay?

Hendrie: Exactly.

Thorndyke: And so that's what we did and we brought out then the—and I pointed out to people I says,

memory is computer memory. When you say memory, okay that's a semiconductor memory or some

kind of a memory. No, we’re in storage; so it’s a storage module drive.

Hendrie: Right.

Thorndyke: But it was lightweight because one of the guys had proven you don’t need a heavy mask

that most disk drives have. It was a very lightweight frame.



Hendrie: Now how fast? What was the resolution as to the rotationals?

Thorndyke: Oh, 3600 RPM.

Hendrie: Thirty six because thirty six makes sense and faster is better.

Thorndyke: Yeah we also had experience with voice coils because I’ll get an IBM lawsuit which goes

back prior that says, okay we got a voice coil drive, 3600 RPM, replaceable pack.

Hendrie: Yep.

Thorndyke: And we put that in the marketplace and we did one more thing; we had learned how to

drastically reduce noise. One of the things we learned at CDC is early on is to make suppress—how you

suppress noise. You suppress noise by reflecting the half wavelength back on itself.

Hendrie: Okay, just like your Bose noise cancelling headphones.

Thorndyke: And so that's right, and just reflect it halfway back, and like a breakwater.

Hendrie: Yeah.

Thorndyke: And so as such, CDC was a standard; everybody was designing against us; we brought out

a disk drive that you set a ho—in a room and you can't hear it; really can't hear it. So as such, that

became the storage module drive. Now there was an awful lot of criticism about that, because it didn't

sell. Well, the reason it didn't sell is everybody had to design a new controller for it, so you got to end up

saying, well you've got six months before they can evolve a new controller for this device, as good as it is,

as a growth for the existing the 2-3 disk unit, that was slow. Once that took off, then it took off and it was

a barn burner in sales and it lasted almost 8-9 years.

Hendrie: Wow, okay.

Thorndyke: And then the next one is now we got this big 6638 or this 808 disk file with big 26-inch disk,

and decided that when you look at that IBM pack it says well, you know if we were to build a double sided

IBM pack, we would have the same equivalent capacity as one of the stacks of the big file.



Hendrie: Okay.

Thorndyke: And I'm sorry no, it would have been the equivalent capacity was 4, the whole 6638 I could

put on a 14-inch disk if I had ten of them. So we designed a double high actuator, with a voice coil and

that became the replacement for the 6638. Now the 6638 cost us about $150,000 to build, the 808.

Hendrie: Yes, the 808.

Thorndyke: This device cost us about $10,000 to $12,000 because it’s common. We sold it for $85,000

as against 400 and also it had a reliability and had replace ability although we never used it. It had

replace ability if you wanted to use it and so then we come up with another device that we felt Arden Hills

should buy and Arden Hills was flexing their wings and so they were out proposing that they would start

buying the disks from somebody else.

Hendrie: This is for the Arden Hills <inaudible> buying the systems.

Thorndyke: For their computer, for their computers.

Hendrie: CDC computers.

Thorndyke: Even though we were selling the device, they said oh no, we got competitive bids outside,

so we’re going to go outside and get the unit.

Hendrie: Okay.

Thorndyke: Well rather than go to the ____________ where you tell Christianity [ph?] I got a call from

Bert [ph?] who was probably number two man in CDC, and he says, “Hey, so and so needs a job. Now

he was a super salesman that sold Seymour the semiconduct—he worked for a semiconductor company

and got fired because he was too alcoholic. He stuck his nose in a bottle. So he went through rehab; he

come out and he needed a job. So I says yeah I’ll take him on. He says, “Lloyd, can't you make room for

him because he did CDC an awful lot of help, he really helped us,” and I said sure so I got him over there

and I says, “Listen, I want you to be my personal salesman, like Harold Brooks; I want you to go to up to

Arden Hills, where you sold before, you sell them this drive and this drive and this. That's the only two or

three things I want you to do.” I says, “No alcohol, you've got an expense account to take them out, but I

don’t want any drinking whatsoever, either them or you and see what you can do.” Well in three months,

he sold all three devices into Arden Hills, because there was a salesman in there selling now rather than

somebody telling them.



Hendrie: Yeah, exactly.

Thorndyke: And then all of a sudden comes the big bitch, says, “That Thorndyke’s got a salesman,

that's illegal; he’s got sales internally; now that's illegal, we’ve got to have him.” So then reluctantly I dug

my heels in and hollered and yelled and screamed and threw a fit, knowing that I was going to sell him to

the marketing side, but I wanted to make sure that he was—got a job they wanted him in, rather than

wanting me out. There’s a difference; I want to take him away from you, but soon as I get him; I'm going

to get rid of him. No, I ended up selling hard, and had my feet dug in and finally they promised him a

good job and I said, “Go over there and interview, but make sure there’s commitments that you're going to

have a job and they’re going to use you,” and he did. But that sold them so that Arden Hills then really

got off the kick of trying to <inaudible>.

Hendrie: Go buy outside.

Thorndyke: Oh yeah, yeah. That's internally, so anyway, come the—back to the IBM lawsuit.

Hendrie: Oh yeah, okay.

Thorndyke: CDC sued IBM for monopolistic practices.

Hendrie: Yes.

Thorndyke: And God we got the notice and says, “You can't throw anything away, you’ve got to keep all

your waste paper; you absolutely cannot throw anything away.” Well, we believed them, so we had sacks

and sacks of paper that was given to the legal people because you can't throw it away. Engineering wise,

I don’t know about manufacturing, mainly engineering and then over time, they come in and of course

they brought in the we are next to the Minnesota cemetery, the Veteran’s Administration cemetery...

Hendrie: Okay.

Thorndyke: And one day about 10 big black limousines come roaring down the avenue, and we were

only a half mile south of the cemetery and we look out the window and Norris says, “Well there must have

made the wrong turn.” They pull up and out start piling lawyers and it was the IBM lawyers coming in to

do the exchange and data, you know, they exchanged stuff.

Hendrie: Yeah signed <inaudible> it’s all discovery.



Thorndyke: Discovery.

Hendrie: Right.

Thorndyke: Well I was—had moved into a small, abandoned automobile sales area and so they went

through it and everything was on and all of a sudden one day, someone found us. And the next day, the

guys showed up and I had about three—

Hendrie: Someone being who?

Thorndyke: Well someone being the IBM lawyers.

Hendrie: Oh the IBM lawyers found you, yeah.

Thorndyke: And I had probably about four file cabinets full of design data from the time we started, and

the guy pulled out a couple things and walked over the telephone, he called up and he said, “I finally

found the stuff. I finally found something.” And so they come out and copied everything I had, but then in

copying it, they made sure they scrambled everything when they put it back together. They scrambled

reports, and intermixed them and did everything else as harassment.

Hendrie: You're kidding?

Thorndyke: No, that's a—but you couldn't do anything about it. We should have been on top of them,

supervising; we weren't. But most of the stuff was programs or 2, 3, 4 years old.

Hendrie: Okay.

Thorndyke: And so then some time later, back when I was now in Normandale, here come a stack of

information kind of in a big couple of boxes; no address, from California. You open it up, it says,

“Confidential, IBM’s new product.” And he started looking at that thing and it says, you know, and this is

John Tisworth [ph?] was then Division Manager; he was my boss; he looks at it because he had been

through similar stuff with Lear and he was with Learjet all of the Lear, Mr. Lear. And he says, “You know,

we don’t belong this; call up our lawyers.” So he called up the lawyers and they come running over and

they just went, “Oh my God, you don’t belong to this.” Then they called up the post office and found out

exact time that that guy delivered that package to the front door, the exact time that we had access to it,

before they come along, got affidavits for that and then they took it and put it in bond and finally returned



it to IBM and later on the lawsuit was settled, and Peripheral got thirty million dollars to do peripheral

research for IBM. Now I was out of Normandale again on camp staff as kind of Chief Engineer and so we

started looking at it and says, well we don’t know enough about voice coils. I started experience with

different—a partial half rotation electric motor as an approach and also prior to that, I should go back a

second, while I was out of CDC building’s quadra _______ that as I started looking at the growth in disks,

I'm saying well how do you make a 10 megabyte disk? Well I can't saw the damn thing into quarters.

The only thing you could do is reduce the diameter until you got down to the current recording technology

at 5 megabytes. Well that was an 8-inch disk, so it’s half the tracks and half the density; one fourth the

capacity. So if each disk is 20 megabytes, this one is 5. So I built a 5 megabyte disk; single disk and

with a in our case, I used a linear actuator; I didn't use a rotary actuator because that was too early yet.

And...

Hendrie: Voice coil linear actuator?

Thorndyke: Yep.

Hendrie: And just one disk in the...

Thorndyke: Just one disk, one platter. You could take it off, put another platter on.

Hendrie: Oh you could?

Thorndyke: Yeah.

Hendrie: Wow.

Thorndyke: You could use both sides of it so we—and I presented it to the management and Camp’s

position was there’s no market.

Hendrie: <Laughs>

Thorndyke: Well there's no market because nobody was selling one.

Hendrie: That Camp has a little problem didn't they?



Thorndyke: Well yeah he had a problem because he felt that he was the only guy that could invent

things.

Hendrie: Wow.

Thorndyke: He was a terrific salesman but his position was that the best defense is a good offense and

so Tom was remarkable in many cases but Tom had an ego that was pretty good. He wrote a book and it

should have been, How Great I Am, but that was not the title. So anyway, we got along. I didn't have a

problem with Tom. He favored manufacturing. Engineering were tolerated; but we were tolerated

because we really didn't report to him; when push come to shove, we didn't listen to him.

Hendrie: You didn't have to listen to him.

Thorndyke: Didn't have to listen to him because we had the guy that had Norris’ ear.

Hendrie: Yes.

Thorndyke: Not only that but...

Hendrie: It was still there.

Thorndyke: But he was also smart because he ended up doing the research; any time we were into

something, he’d be over the Hill Reference Library doing research for us for three or four days at a time;

like we wanted to start painting disks. Well, how do you paint a disk? How do you coat a disk? Well if

you spray it, you get statistical bubbles. How do you get the stuff on; one way or another? Well it

evolved that spin coating is the most reliable way of painting and...

Hendrie: I was going to say, you pour it in the middle and turn it on.

Thorndyke: Except it’s not that easy.

Hendrie: Right, okay.

Thorndyke: What evolved is the fact that we could spin coat and we could have it trapezoid from outside

in, from inside out, concave and convex, based upon spin speeds, and solvent volatility and so we could



make any damn type of coating we want and thinness. My arguments are that we no longer painted the

disk, we stained them because you could look through the coating and see the material underneath.

Hendrie: Because you could make it that thin.

Thorndyke: We could make it that thin.

Hendrie: Okay and then you had the flexibility to figure out exactly what do you really want on it and

make that.

Thorndyke: Yep and ___________, the density is a function of thickness of the coating; the thinner the

coat, the higher the density.

Hendrie: I understand that because the dipoles don’t fringe.

Thorndyke: Yeah, right. And so at any rate, I was a—the result was that with the IBM money, then we

started exploring methods, such building better platers or better coaters and we developed ability to

analyze a surface with capacitive probes so that we could digitize the surface and look at the basically

wavelengths, and find out that when the machining tool got dull, it started putting vibration patterns in,

which were near the natural frequency of the head, which means your head will crash and so we had to

continually probe them and soon as they begin to see those start to change the tool and so what you did

the tool is the disk just unloosen the screw, turn the disk a quarter turn, tighten it up, you've got a brand

new tool. So the capacitive probe then guaranteed that we did not have vibration frequencies that are

near the natural frequency of magnetic heads.

Hendrie: Wow.

Thorndyke: All based upon IBM’s funding; we’d write them reports and I think they threw everything

away.

Hendrie: Yeah now you did have to—the deal was you had...

Thorndyke: We wrote them reports; we wrote them reports.

Hendrie: You had to write the reports and give them to IBM, yeah.



Thorndyke: Yeah and so...

Hendrie: But you were totally free to use anything you discovered.

Thorndyke: We totally free to do anything we wanted, yeah we got it also and part of that was I was

convinced that back at Univac, we used an angular positioner and so I was convinced an angular

positioner was a way to get into the small disks.

Hendrie: Ah.

Thorndyke: Or rotary actuator.

Hendrie: Yeah what’s called a rotary actuator now.

Thorndyke: Right and so as such that was developed and that went with the 8-inch disk and then while I

was at Normandale, I put this into the 8-inch floppy and then we sent all of that out to Hawthorne as when

we acquired the NCR stuff and Hawthorne then was merged with Oak City when Honeywell went out of

business.

Hendrie: Right and there was that Honeywell/Oak City thing.

Thorndyke: And NCR was, well they was really close with CDC; they had decided that they were going

to invent new technology and build this cheaper than IBM could build them and they’re going to do it by

using a mutlitrack head, which they’re going to build a head for like 10 cents a track. Well heads are

about a buck and a half to five dollars a track, depending on what you've got and so they had about an

inch and a half head with a hell of a mess of tracks in it. Well the problem with an inch and a half head,

the disks are not perfectly flat so even though you're saying they’re floating, you've got different

variations.

Hendrie: The altitude is not—even though it’s flying, it isn't all flying at the same altitude.

Thorndyke: Not only that, but then they decided that they were going to plate the disks. And all of a

sudden you've got a metal head and a metal plate and you've got gallwing [ph?] failure, you cannot do

anything about it unless you end up putting on some—a blade [ph?] of coating, you're going to have

gallwing failure; head to head causes a gallwing failure.



Hendrie: Yep, okay.

Thorndyke: And so as such, when you put an oxide disk on, you've got a binder that will just char, will

burnish, but it doesn’t end up killing it and so we went out there. The meantime, between failure of the

disk was 9 months. Now they’re going against IBM. What they had to do is put in 2 disks; because they

didn't know which one would fail. And so they sold the whole thing to CDC and I went out there and we

finally—we scrapped the whole line; we didn't want to plate disks or anything else; we scrapped the whole

line and transferred out our small disk products into unit, and finally got...

Hendrie: Into their factory.

Thorndyke: Into their factory and using their engineers and since NCR was interested in small capacity

devices, manufacturing wanted to get rid of the big drive because it was difficult to make and I finally had

a—ended up talking with a couple people, Mr. Norris including and said, “Look at, we’ve been building

disk drives for ten years, we can hardly build a damn thing ourselves, what do you think is going to

happen when you send it out to NCR who has never built anything good in their life in this capability. You

can guarantee it will be a failure; they’ll never be able to produce it ever.” And I says, “The thing is, you

keep the most technology challenging next to engineering and you take the technology least challenging

and let them learn it.” Least challenging is a small disk and that's the one they want and therefore it’s in

their factory; they’re paying for the factory, so they can get a disk a hell of a lot cheaper than they could

buy it at any other place and so that's what prevailed and so with the lawsuit. But after we sent it back

and to IBM, then right away, their position—well you copied it. You ended up making copies of it and

you're using our technology in your new disk drives. So CDC invited two or three IBM engineers to come

in and do an audit of all of our disk designs.

Hendrie: Wow.

Thorndyke: Come in and do it; come in and go through and write a report. They come in; went through

and it says, “They are using none of our technology approaches. Everything is developed internally;

everything is developed based upon their heritage.” And when the lawsuit was settled, we were told that

had we not handled it in that way, that that would have been the coup that ruined the lawsuit. We would

have lost the lawsuit based on the fact that we had stole that technology.

Hendrie: So did anybody ever figure out how those documents got sent to, you know, there’s conspiracy

theory that would say that the IBM’s lawyers sent it.

Thorndyke: Well, I never thought of it that way.



Hendrie: Like a bomb, you know?

Thorndyke: Yeah, no they traced it back to some people internally that was selling it.

Hendrie: Oh, and they were selling it.

Thorndyke: Yeah they were selling it to other people and such why so they were theft of trade secrets.

Hendrie: Okay.

Thorndyke: Now not part of it, but as a result of, we had a love-in with Hitachi and Fujitsu on technology

exchange for years and part of that technology exchange was a raft [ph?] including a high performance

computing technology and peripherals.

Hendrie: Okay.

Thorndyke: And one of the guys, I can't remember his name right now was kind of the—not quite the

Seymour Cray but that type of recognition within Japan and he was always interested in the 3330; what

the hell is a 3330; you got any information on the 3330. We said we don’t need it. We’ve got our own

heritage; we risked going down this line this way using the heads that we designed and other stuff and

we’re going down this way and he said, “Well you know, we’d certainly like to know more about the 3330.”

And we had one of our corporate people brought it Palin [ph?] and Associates. Now Palin and Associates

was an industry consulting group and their claim to fame was they could tell us what IBM’s doing before

IBM announced it. But none of us trusted them, because they wanted to know where the hell we were

going and everything else.

Hendrie: They wanted to get your information and they were going to sell yours to somebody else.

Thorndyke: And so we said no, we refuse as ETA to meet with them and talk to them at all, but it was

brought in by an IBM this Bill Morgan brought them in, the same guy. And so they brought in a couple

guys with them, claimed they had no responsibility; both of them from Stanford and we find out six

months later, Stanford was designing a supercomputer based on CMOS which was about two years

behind us and here he was in there as a non-disclosure and everything else, listening to what we talked

about the advantage of CMOS, and why we’re going to CMOS, and why is CMOS that makes the only

sense and that it’s blinking now.



Hendrie: Yeah.

Thorndyke: So the fact that Palin Associates, then when the I think it’s Hitachi, no Fujitsu announced

that they had an IBM confidential manual on the 3330. Now Palin had been working with Fujitsu for 15

years. Palin was a spinout of IBM. They left IBM and they became a consultant. Palin thought it was

their responsibility to go tell IBM that the Japanese have your confidential manual on the 3330. They

says, no wait a minute, now your conspiracy theory comes into play.

Hendrie: Yes.

Thorndyke: Palin was spun out by IBM to find out what the hell’s going on in the industry.

Hendrie: Right.

Thorndyke: I'm certainly convinced of that and so what they wanted to do; they wanted to see a 3330,

so it was arranged that they could go and see a 3330 if they would go in on a Saturday night into a Pratt

and Whitney plant that had a 3330.

Hendrie: Okay.

Thorndyke: Well Pratt and Whitney plant is a government facility; they went into a classified government

facility as non-classified people; they snuck in, they stood in a room, they were photographed on the way

in, they were photographing the room, a guard conveniently walked by; they laid down on the floor so

they couldn't be seen; they opened the 3330 up and took pictures and stuff of it, all of which IBM arranged

as a capability and IBM collected 5 billion dollars from Fujitsu for theft of trade secrets.

Hendrie: Oh, with these smoking guns!

Thorndyke: Yeah this doctor, whatever his name was, disappeared from Fujitsu and we thought he was

probably running a ball bearing factory or something; he just disappeared and I don’t know if he ever got

canned or what, but he just disappeared. But anyway, so that was a result of our interchange and so I

used to go to Japan every six months; spend a couple two-three days in the different plants and see what

they were doing and how they were doing it and the thing that's interesting with the Japanese, since

they’re smaller people, but they’re competitive so I’d order a scotch, hammer it down, order another

scotch, hammer it down and so they’re keeping up with me. Well after three drinks, they can't find their

fanny with both hands.



Hendrie: I know because there’s this theory about alcohol and weight <laughs>.

Thorndyke: Yeah they couldn't find their fanny with both hands. Then you'd ask a question, you'd start

getting honest answers.

Hendrie: <Laughs>

Thorndyke: I said, well I don’t understand. He said, you can't build that chip the way you're talking; it

doesn’t have enough ground planes.

Hendrie: Yep.

Thorndyke: He reaches in his thing and pulls out the chip and starts showing me the ground planes and

how they’re handling the ground planes so that they can in fact get by with the stiffness of the ground

plane. It’s an area that we’d never think of building that way.

Hendrie: Oh wow, so, you challenged them? You give them three scotches and get the answer, wow

that's <inaudible>.

Thorndyke: But we never, we never did it that way because we simply put in more ground planes, but

they used all sorts of stuff in ground planes but they were very inventive. The thing that you'll find at

__________, when we converted to CMOS, no one ever felt CMOS would be a high performance

computer chip, however, when we analyzed the market, it says that you have to have your main logic chip

in the main stream of production which is a memory wafer. So we had to go with a memory wafer in order

to get the chips; otherwise, we went from the old computer, you bought about oh probably 50 or 100

semiconductors per every memory chip. When you integrated the circuit, now you've got hundreds of

memory chip for every computer chip. Now the computer’s all on the chip. So the problems are, the guy

says, I can't afford to build your computer chip. And the implications are that well if I had a memory order,

then I’ve got to build your computer chip in order to sell the memory.

Hendrie: Yes, and I could do that. I’ll figure out how to do that.

Thorndyke: See, they can't say you've got to do this; it says that I had to come back to them and says,

we would buy this many memory chips if you would produce this N number of computer chips. Different

areas that Control Data was into beyond computers and we had all sort of a happy employee is a good

employee and so we had all sorts of functions to make you happy. If you were disgruntled because your

kid is on drugs, we've got someone who will—we know how to go out and counsel drugs and this and that



and everything else, but effectively, we started our own social welfare program if you wish, almost and

diverted money into it.

Hendrie: Now was this Norris’ idea?

Thorndyke: Yeah, well some of us felt he was writing his eulogy.

Hendrie: Oh, okay.

Thorndyke: And I don’t have a problem of him going into minority areas to hire people; I don’t have a

problem. A lot of people had problems, but I don’t have a problem with that because they—you've got to

educate them so they know how to hold a job and have a responsibility of a job and my feeling was that I

felt that I wrote a proposal to Norris that says that for every hard core unemployed that we hire, why can't

we get a tax reduction for their cost without going—paying money to the welfare system, which half of it

goes to people that are not involved, but I said, why can't we get a—let’s assume they were going to pay

the guy $30,000 a year and why can't we get $60,000 a year as a tax—actual tax reduction to the state

that we hired one. And we teach them, teach them discipline, teach them the fact what you do to work

but that didn't go anyplace. But my feeling is that like we down in Mississippi the fact that given a chance,

they learned the rules, it’s great. We had a rule down there; if you're absent or tardy three times in a row,

you're dismissed. So now we’ve got these new kids in and these 25 year olds, plus or minus. She’s

tardy; so you give her a reprimand; she’s tardy the second day; you give a reprimand, and third day you

send her to the personnel to be terminated. Well I had hired a black personnel woman in personnel now,

and this is a plant. I digress for a second; I hired a black accounting and promoted a black girl into

management. Here’s the accounting girl or the personnel girl’s a black and one of my close friends that I

knew pretty well one day asked me out for lunch and he says, “Lloyd, I know you walk around the

neighborhood to get exercise at night,” he says, “If I were you, I wouldn't do that anymore.” I says,

“Why?” He says, “We feel differently here about the integration than you do,” and he says, “You’ve done

more than anybody’s ever done down here in a plant.” And as such I’d stay out of redneck bars from now

on and I wouldn't go walking around the neighborhood at all. You want to walk, go over to the superstore

and walk around the inside of the superstore two or three times; don’t walk over or drive over.

Hendrie: Wow.

Thorndyke: I understood the message. I understood the message and it wasn’t him it was just...

Hendrie: Yeah it wasn’t him; he’s thinking about you.



Thorndyke: He referred it, but anyway, my feeling is that yeah we’re going to have equal opportunity

and we’re going to have a minority mix and that plant went that way. But anyway so I didn't have trouble

with CDC starting the plants because it, over time, in Minneapolis, we had a plant that trained people and

after it trained, problems existed; they didn't go out to the plants and get a job. So he has some guy

come in and the guy says, “Well, none of them got transportation. They don’t have any money to buy a

car or anything.” He says, “Okay, tell the bus company that we want to pick people in the plant and go

south to the plant and go north to the plant. Get a school bus so we want a school bus to pick up people

and go south and north and pick them up in the afternoon and go from south to north and back again.”

So to and from the minority plant, because the minority plant was a walking plant.

Hendrie: Yes, okay in the city?

Thorndyke: In a minority area. Now the interesting thing is what he put in is a day care center because

a significant number of the women were single parents so he put a day care center in and staffed it with

Plato terminals so the kid could begin to work on Plato terminals. And then Humphrey come along and

said, “Oh my God, the government’s got to get involved.” He says, “Go to hell, government. Go do your

own thing. You're not getting part of this. You're not getting into it at all, because you wouldn't run it

right.” So therefore then they could bring their child to the day care center, take the job out south, come

back, pick them up.

Hendrie: That's cool.

Thorndyke: Until they got enough money to buy a car and other things and they gradually weaned them.

So anyway but one of the problems that we saw after we did the Cyber 205 and started planning the next

generation machine based upon an integrated circuit and CMOS.

Hendrie: Did you know you wanted to use CMOS right from the beginning?

Thorndyke: Well, Tony Bachman [ph?] will go into it, but we knew the advantages of CMOS because of

the Moore’s law of scalability, since the CMOS is a capacitor.

Hendrie: Yes, I understand.

Thorndyke: And you've got a four to one shrink; and every time you shrink it, it speeds up and also we

wanted to have it on the main memory wafer because you cannot have successful logic if it’s not a

successful memory technology. That's why Seymour was doomed to failure; he never had a gallium

arsenide memory. There was nobody had a gallium arsenide memory so you had to pay the full cost; the



total cost for developing that was never borne by a big memory volume. And so that was—he’ll go into

that but anyway, the net result was that we weren't getting anyplace, there's not enough money to do a

program and yet we didn’t kill the program and so we sat around and they finally come to the realization

that we had to spin the supercomputer business out of the CDC; there was too much bureaucracy, every

time you wanted to do something. I was brought up before an inquisition because we had IBM guys

come in and convince management that we had to have a phase review system and IBM uses a phase

review system that was on a product where any particular department, if they objected to the product

introduction, then they could stop the product introduction. Well when you're producing 500 terminal

systems a day, you need such a deal. However, we’re only producing one supercomputer every six

months, so what the hell’s a phase review system? One of the comments are that you had to be able to

have three computers worth of spares and you had to interchange all those spares in the computer and

have it still work properly in order to ship. And I says, “Why?” You know, it will take us a year and a half

to test that way, but there’s only one computer and it’s already paid for. But the phase review system,

there’s no distinction between the high volume product and a volume product, a low volume product; low

cost volume product and so I delivered the Cyber 205, I’ll go through a phase review system and of

course then all the departments they harpooned me and I was told the next time that I did that, I would be

terminated.

Hendrie: By who, Norris?

Thorndyke: By Price.

Hendrie: Oh by Price; Price had taken over from Norris?

Thorndyke: Right.

Hendrie: Norris had retired.

Thorndyke: No, Bob Price was too much of a gentleman in that he was very, very kind, if you wish. He

never raised hell with you and I saw one of the guys that stormed in his office and he said, “Bob Price, are

you running systems or am I running it?” “Well you're running it.” “Okay, if I'm running it, keep your nose

out.” Well I had that pulled on me, you know, somebody come down and I says, “Listen, as President of

this company, I’ll go where I want, anytime I want, and when I want and talk to anybody I want and as

long as I tell them that when I'm talking to them, I'm not giving them direction; they go to their boss for

direction; I'm in for information. Anything I say is not direction. When I ask you why you're doing it that

way, that's not direction; I'm trying to get information. Your boss will tell you how to do it, not me and if

you try to use me as an excuse, you can't do it.” Well all Price had to do was tell him, “I’ll do what I damn

well please, if you don’t like it then you've got the door.”



Hendrie: Right. Wow, yes.

Thorndyke: And so he never—he was raised as too kind a guy and Norris was blunt. Norris, he grew up

in a farm and so he learned four letter words.

Hendrie: Yes, <laughs>.

Thorndyke: He would use them now and then too.

Hendrie: Okay.

Thorndyke: When that gets turned off I’ll tell you a couple of them. Want them now?

Hendrie: Yes, of course.

Thorndyke: Okay but anyway, so we finally decided that we never had enough money to get started;

you could study but you couldn't end up designing a computer.

Hendrie: Yeah you couldn't.

Thorndyke: And the other problems were that we had developed the simulation technology so that we

could design a computer put in a current supercomputer and operate it with a—you know all of the

instructions, timing and specifications and everything else and so we ended up having a computer inside

a computer and you could even run software against it.

Hendrie: Yep, okay.

Thorndyke: So as such, out of that come the ETA-10, so but the problems were that the I don’t know,

systems got mafia, if you wish, or the gestapo sole goal was well, Lloyd, I put in a requirement for 10 high

performance terminals, so will you do the design work and says, oh yeah got 10 high performance

terminals, how many people is that going to replace? And I said, oh it will probably replace 25 or 30

people. Well we’ll approve those 10 terminals, you fire 25 or 30 people, I said, I haven’t hired them yet.

Don’t tell me fire them, I haven’t hired them yet. And in order to get this we have to have those terminals

to do the simulation. I said right now the 205 took too long, because we had a batch process every night,

then we got the printout the next morning, we designed that day, and then get it all ready, do a print out

and submit a batch process that night and you process it overnight. I says, we got to have turnaround



time. I tell you, there’s so many submissions before the end. Now if I could get five submissions a day, I

can produce it in one-fifth of the time that I did with 205. And so we need to buy some high performance

terminals; we also need a supercomputer in house to do the data logging and we’ll keep everything in the

supercomputer and so Tony will talk about that but I finally went to Berg, not Norris, I went to Berg.

Hendrie: Who was Berg?

Thorndyke: Norberg was head of personnel; he’d been with Norris a long time and he’s really Norris’

confidant if you wish and so Berg and the reason I went to Berg, I knew him pretty well and I felt if I went

to Norris and he said no, we were done. However, if I went to Berg and Berg would front run it, then in

fact, I could go to Norris if it got torpedoed.

Hendrie: Yes, okay.

Thorndyke: And so that was a—because Berg would be a champion which is great for us, because we

didn't give a damn how we got it done and out of it come the fact that the Control Data was going to spin it

out so I got called in Price’s office and he sat down, he says, “You’d submitted a proposal to spin it out.”

He says, “Do you want to run it?” Well, now you sit there and says, “Well you don’t take much time to

think about it; you don’t stall around and say well let’s negotiate.” I says, “Yes.” That was it.

Hendrie: Okay, wow.

Thorndyke: So we formed ETA within CDC and we were scared to death that it would leak and so sitting

around and finally I decided well, you know why don’t we end up giving everybody a piece of paper that

says you're now privileged to a highly classified or secret program within Control Data that if it leaks to the

public could adversely affect the Control Data stock, plus or minus and as such if that leak is traced back

and we’re sued, you are going to be personally liable and CDC will not support you in any way, shape, or

form.

Hendrie: Okay.

Thorndyke: So you sign this; and they signed it. We ended up starting with 130 people and my boss

never come to that we were doing it for 3 months.

Hendrie: Wow.



Thorndyke: And I had one Vice President who was known to have a verbal diarrhea and he says, “I got

to know what you're doing, Lloyd.” And I says, “You're going to find out that the worse thing that

happened to you is know it; know what’s going on.” “No, you tell me!” And I says, “Fine, now here’s a

piece of paper, you sign it.” “I won't sign such a thing.” I says, “Okay,” I says, “if you don’t sign it, I’ll tell

you what we’re doing and I'm going to Norris and tell him that you would not sign this piece of paper after

I told you—or even before I told you what we’re doing.” And, “Oh..” and I says, “We’re going to spin out

the supercomputer business.” And as such, you have now been told a company secret that you have to

make sure you do not end up telling anybody about it and so we ended up operating for 3 or 4 months,

hired 120 people before anybody found out about it.

Hendrie: Wow, that's good.

Thorndyke: But it also made enemies. Now we got enemies out our kazoo and CDC then, one of the

things we never solved was the conflict between our marketing and CDC marketing. CDC marketing was

supercomputer people and we were now the supercomputer company outside and so we were prevented

from talking to any CDC customer that had an active CDC salesman so we couldn't sell any

supercomputers and Price never solved that problem. I even cited a couple times that said, you know

that would be an interesting case study for the is it Wharton School that does the case studies?

Hendrie: Oh, Harvard does case studies, lots of them do, yeah. They write them at Stanford, they write

them at Harvard, they write them at a number of places.

Thorndyke: Says that would be an interesting case study of how the spinout was done and necessarily,

not necessarily approved. Now CDC always owned 90 percent of us.

Hendrie: Okay.

Thorndyke: And we, one of things that Norris required was that the Principal had to have skin in the

game so the 6 or 8 of us put up the other 10 percent but we never solved the CDC marketing interface.

Hendrie: How did you raise the money to go and do this?

Thorndyke: We raised the money from CDC.

Hendrie: How could CDC...



Thorndyke: Because they owned 90 percent.

Hendrie: Okay but they couldn't afford to do it themselves; oh I see, it would look on their bal—I

understand. It would come—they would have to take it out of profits; if it was inside by making it a wholly

owned thing, they could just use their cash on hand or...

Thorndyke: Right and the other thing at CDC ended up then transferring like a computer to us, but that

computer was essentially written to zero as they traded in on it so we ended up getting a lot of stuff that

way which has zero cost.

Hendrie: Yeah it was a trade in to CDC.

Thorndyke: Yeah and it depreciated immediately because it was a trade in so you got a fair amount of

that, but then we bought a mess of terminals and really started getting turnaround time.

Hendrie: Yeah I read you used Mentor workstations, is that right?

Thorndyke: I think it was Mentor, yeah.

Hendrie: Yeah okay.

Thorndyke: So we ended up producing it in half the time but the simulation technology was so good that

we ended up being able to run the machine in memory and what we put—we had the production up for

the printed circuit line and we ended up enab- to the printed circuit board, we ended up testing the printed

circuit board where we would touch in a starter end of the line, we would touch it with a capacitive probe

and digitize the capacitive probe for a particular line and the computer calculated what that capacitive

should be.

Hendrie: Oh wow.

Thorndyke: So every line was tested for the capacitance and when you went through the big joint, which

was more copper, so that's more capacitance, you'd count that delay, and so therefore you counted the

capacitance and the delay.

Hendrie: Yeah if you know what the capacitance of of every line is you're up what the delay is. You

could do this testing before it was populated with the chips, right?



Thorndyke: Yeah on each circuit layer. Each circuit layer was then tested that way.

Hendrie: Okay got it.

Thorndyke: And then what you did is now you take the two units and says, well wait a minute, this is

supposed to be 10 and it’s 50; where else have you got another 50? So you'd start comparing the two

and you'd find out which two are shorted together.

Hendrie: Exactly.

Thorndyke: And so then you'd go in with a scalpel and cut the line.

Hendrie: Or if it’s a plated through hole, drill out the hole, right?

Thorndyke: Well the plated through hole was really not the problems.

Hendrie: It was literally lines?

Thorndyke: Yeah or you had a flaw in the—we found that since you used the negative; if there was a

speck on the negative, it become a pos- it become a line.

Hendrie: Yes, it becomes copper.

Thorndyke: Right and so therefore, you end up having really clean your negative every time you use it;

not like most people use it time after time after time. You couldn't do that; you had to lay it down for

contact, when you picked it off, you had contamination come with it and so you had to clean that negative

every time.

Hendrie: Wow.

Thorndyke: But that was just a matter...

Hendrie: Yeah it was just something you had to do; that wasn’t a big deal.



Thorndyke: And that was simply a process change because that was different. But we’re down now to

where lines are only about 10 mils apart. Now the other thing that we found is that as you solder down

the chips, so you plate a plating solution on top of it, where you want to solder the chips and the problem

you have is that you tin the circuit; the circuit had 288 pins around that one centimeter square. They’re

about 4 mils wide and 6 mils spacing.

Hendrie: Okay.

Thorndyke: And so we built—they wanted to build a robot; we’ll do it and I says, no, since those circuits

cost me $4,000 a circuit; we’re not having any goddamn robots; sorry, down wrong. We’re going to have

a 98.6 degree robot with a microscope following that thing going on and so we ended up developing- they

developed a unit that had a LED or I'm sorry, a fiber optics cable in this corner and this corner, and then a

joystick you could turn it around and then it looked at the chip and it then put the chip on top of it and it

was orientated until it had a proper fit, set it down, come down with a reflow, four reflows, you reflowed

the thing. We could solder 288 chips in about 4 hours. Now all computers soldered together in 8 hours,

or in 4 hours. We could solder 2 a day. We were only selling about one every quarter.

Hendrie: I know that's a hell of a lot faster; how long did it take a woman in the middle of a ________,

the one woman that would fit in a ________ to wire wrap it? I mean I’ve heard it took 6 or 8 <inaudible>.

Thorndyke: So it was—and the binds are that you had to have that, you could not solder those by hand.

Hendrie: Right you had to do it.

Thorndyke: You had to have it automated. Now, we found out that after it’s all done, we started to put in

check out and we found that we had shorts and so we didn't understand. Well the board was okay but all

of a sudden after we got it all soldered; well the soldering process, the flux evaporates, goes into a gas,

well when it goes into a gas, the solder is moltened, so it blows solder balls all over the damn thing. Any

time you solder you blow solder balls all over. Well, now all of a sudden two solder balls get together on

a small space, it's a short.

Hendrie: Yep, your spacing’s so small that...

Thorndyke: Right and so we learned and we learned and we bought a vapor degreaser; put that

computer in the vapor degreaser and it then took the flux out, because when the flux cooled it becomes

now a glue and so we vapor degreased that thing and after a few times you have half a teaspoon worth of

solder balls.



Hendrie: Okay.

Thorndyke: So we got rid of the solder balls by vapor degreasing it so the check out is you solder the

chips down, vapor degrease it; the next thing you do is you load the chip with the program that does a self

test and there's a single bit processor that does a self test in about 3 seconds; the supercomputer had

already figured out...

Hendrie: What the patterns were to send in.

Thorndyke: Yeah what you load as a test pattern and run through it at speed for about 3 seconds and

you take out the checksum and compare it to what the supercomputer says it should be, and you're about

97 to 99 percent sure that you had a good chip and so as such then we wrote another program that drove

the line driver from one to the other chip and you made sure that you had a continuity to the other chip

and then you go around and say did you get this data pattern and internally in the chip, when you're doing

the self test, there’s a short from the driver to the receiver so we could see that the driver was working.

So anyway, there was all that sort of stuff and then finally the timing was done. And the timing was a

clock period was staggered; because within the chip was all DC, so you wrote the chip to go DC, if it

needed a clock, it’d generate it’s own clock but a major pulse started the chip to run as DC logic and it

gets all done, generates it’s own clock and then it comes to a screeching halt. Well that says that if

you've got a critical path then everybody else can be delayed depending upon when they finish and so

then you back up for a safety factor and that's when you start them. You don’t start everybody with a

clock pulse, because if one needs only half the time, then you'd delay it a ways so you don’t have as

much ground current because every time you look at it, you've got a hellacious ground current in CMOS.

So Tony will go into that for you.

Hendrie: Okay good.

Thorndyke: But it was uh.. the thing we had trouble solving was the market, because CDC wanted a

market; they couldn't sell it, then we’d take it back and start selling it and immediately CDC become

paranoid again. In the meantime, Control Data was designing 5 different computers, 5 different totally

independent computers, independent everything. We had one that was identical and we could take the

fastest computer and run it slow and it didn't make any difference and the diagnostic, maintenance,

everything is identical; not only that, but we could take a computer in Europe and run diagnostics from

United States.

Hendrie: That's really good; cool.



Thorndyke: And the replaceable module was a computer, it was not a—and so a customer engineering

comes along and says, well we’ve got to have a printed circuit board and then we’ll have that and then

we’ll send the chips, I said, “You don’t understand.”

Hendrie: You can't do that.

Thorndyke: It cannot be done.

Hendrie: You cannot replace the chips.

Thorndyke: We want a computer in the manufacturing area that's assembled and if we need a circuit

board or something else, we’ll take that out and send it to you, plug it back in and this will be your spares

and if we need the computer, we’ll take the whole damn board out because this board is working.

Hendrie: Right.

Thorndyke: The thing we’d come the realization that the spares reliability was no greater than the on

board life of the unit.

Hendrie: Yeah.

Thorndyke: So therefore, you had a failure, you had high probability the failure will be in the spares as in

the machine, except the machine is better because it’s immersed in liquid nitrogen and that may give us a

very constant temperature.

Hendrie: Wow. How did you do the—when you immersed it in liquid nitrogen; you know the machines, I

know you sold them both ways, but the ones in liquid nitrogen, how did you rejuvenate the liquid nitrogen.

Did a truck have to come up every week and deliver liquid nitrogen?

Thorndyke: We had two choices. One choice was we recovered the froth and recompressed it and that

took a 50 horse motor and then you come across the fact we used about, as I remember about 2 gallons

of liquid nitrogen an hour and that's not a lot. Now liquid nitrogen cost us 0.35 cents a gallon.

Hendrie: I know what you do.



Thorndyke: Yeah so we come to the realization, you boil it off; you just boil it off and just keep—and we

had about a 2,500 gallon—no it’s got to be more than that; it must be 25,000 gallon tank outside full of

liquid nitrogen. We were buying in some cases a truck load a day, depending on how many machines

were in check out but the liquid nitrogen, my arguments are after being around it that the people

designing air conditioning systems for say, auditoriums and stuff should not end up designing the system

so that the Freon system carries it. You should design it for a normal use and then bring in liquid nitrogen

as a backup, because it comes in at 77 Kelvin and you can raise it up to 270 degrees Kelvin is zero and

so therefore, you could end up having a hell of a lot cheaper, because supplemental, you don’t need to

run it 24 hours a day, you design it for 10 percent occupancy for the system, and then you bring in the

backup.

Hendrie: That's an interesting.

Thorndyke: No one’s ever done it, but the problem with liquid nitrogen is they waste product. When you

do a liquification, 78 percent of the fluid liquefies as liquid nitrogen.

Hendrie: Right and...

Thorndyke: And there’s no use for it. Now they're starting a use for it; the oil companies are using it for

fracking, that's when they drill a well, instead of using hydraulic, high pressure hydraulic, they bring in

liquid nitrogen in a big burner and turn it into a gas which as it converts to a gas now you've got high

pressure and so now you're using a high pressure gas by heating, heating liquid nitrogen. You bring in a

tank of liquid nitrogen and a big blow torch and now you've got hot gas down at such a high pressure that

it does the fracking for you.

Hendrie: That's an ingenious idea.

Thorndyke: Now that's been around I think a few years.

Hendrie: Okay, alright.

Thorndyke: But it's a drug in the market, and what you're paying for is the truck and the driver.

Hendrie: Yeah and the oxygen is what the plant is selling for.

Thorndyke: That's right and the rare gases.



Hendrie: And the rare gases, yes. The oxygen, the helium and the hydrogen.

Thorndyke: And if you want to liquefy helium, it takes 10 gallons of liquid nitrogen to liquefy one gallon

of helium.

Hendrie: Really, wow.

Thorndyke: And so effectly, that goes on.

Hendrie: Yeah. Alright well.

Thorndyke: It’s quarter to five.

Hendrie: Yes, I sort of—I think I should start wrapping up.

Thorndyke: You think we’re done?

Hendrie: I don’t know. I don’t think—I think we could go on forever.

Thorndyke: I got that impression too.

Hendrie: You get that feeling? Uhm.. the and have fun doing it but I think we need to wrap up now, and I

really want to thank you, Lloyd on behalf of the Computer History Museum for taking the time to do this.

Thorndyke: Well, as I say, it’s the Gawin [ph?] has been after me for quite some time to get it down.

Now Tony has written a Vargas I think his name is, out of Canada has written stuff on Control Data, I

think it’s Vargas, he’ll know the name. Well Tony has written a lot about ETA on some of the advances

and everything else and he allowed him to have an advanced copy to edit it; he saw fit to publish it and so

Tony is spastic about it, because it was not written for publication but he was interested in getting his

name out in front of everybody else and that sort of stuff.

Hendrie: That's not good.



Thorndyke: And so but Tony’s got some very good data as to how the chip was designed and why it

was designed the way it was designed and the fact that we had kids lay a chip out and then after they got

laid out, then the experienced lay out guy would go through and start running the chip to find the long

path and then reorganizing the chip to reduce the long path.

Hendrie: Yep.

Thorndyke: And put some of the slow circuits or the circuits that were vastly too fast, stretch them out,

slow them down, as you concentrated the unit and he usually doubled the speed of the chip.

Hendrie: Wow, that's pretty darn good.

Thorndyke: By basic reducing the lays on the chip.

Hendrie: Yes, okay.

Thorndyke: And so there’s that interesting, the piece.

Hendrie: Well I think I'm going to interview him and I’ll...

Thorndyke: Now the state of the art when we were doing it we got 20,000 gates which means we

probably had 100,000 transistors or more. Current state of the art is three and a half billion.

Hendrie: I know.

Thorndyke: But the point was that every lithography shrink did not require you to change anything.

Hendrie: Exactly.

Thorndyke: It was free.

Hendrie: Yeah, no it’s wonderful; it’s a wonderful technology.



Thorndyke: Now that I see it’s blinking now and not only that, but Tony, we felt that since the board was

laid out with an X-Y coordinate, that you could end up taking a coordinate of one layer and take the long

paths and go on a hypotenuse so you could take one more layer and hand lay out the short paths, or the

long paths, and eliminate the board and take your long path and have a higher performance computer.

We wanted to get down to less than 5 nanosecond total time. Now the way the computer was designed,

you run a chip for a clock, or you run the board for a clock, you're not on the ship and the board.

Seymour’s design is you're on a chip and the board. Well therefore, if the circuit slows down, you've got a

problem; now you've got something has to change. In our area, that there is a chip that determines the

timing of every time on the—when the clock starts on a chip because after you get on the chip, you stay

on the chip, and so that anytime the computer gets in trouble, first thing you do is slow the clock down,

now it goes back working again, so you've got a fail soft system.

Hendrie: Yeah, that's—

[recording ends abruptly]

END OF INTERVIEW

oral history of lloyd thorndyke; 2011-07-12

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