# 05 2015 Vol-21 Radio Movies, television as invisioned in1924 as reported by David Wilson

The NAB 2015 Report by observer Richard Majestic

Next meeting/Spring Picnic May 17th at the Quelab Theme: Food, drink and tailgate auctions

In the 1920s there were no TV's so the people would listen to their radios. When the people tuned it they could listen to comedy shoes, news, live events, jazz music, variety shows, drama, or

oprea. By 1923 nearly three million people owned radios. Radios were also used for newspapers being read so that the people could know what was going on. By 1922 there were 600 radio

stations. In 1921 Chicago got its first radio station called KYW. It played Opera six days a week. After the opera season ended they started playing different things, popular music, classical

music, sporting events, lectures, fictional stories, newscasts, weather reports, market updates, and political commentary.

Radio Movies: Will radio and the motion picture combine? By David Wilson

In a 1924 Motion Picture Classic Magazine I recently purchased I found a story titled: Will radio and the motion picture combine? The story was predict-ing the possibility of motion pictures being broadcast like radio via a device called “television.” I’m always amazed at what I don’t know when I think I know it. I guess that’s why I keep buy-ing these old magazines. If someone had asked me who pioneered television I would have said Philo Farnsworth. Farnsworth would have been a good answer if you were talking about the first fully functional, all-electronic im-age pickup device called the video cam-era tube and another device called an image dissector. Both these devices were used in what became the first fully func-tional and complete all-electronic televi-sion system. I remembered that Farns-

worth had developed this television re-ceiver and camera system, produced commercially in his firm of the Farns-worth Television and Radio Corpora-tion, from 1938 to 1951. What I didn’t know, until I read this 1924 magazine, was that an America inventor by the name of Charles Frances Jenkins, one of the early pioneers of what became the motion picture projector, was also one of the inventors of television. Jenkins’ version of television was one of the very early ones and it was mechanical, not electronic like Farnsworth’s later ver-sion. According to my 1924 Motion Picture Classic Magazine, Mr. Jenkins had been issued some 300 American and Foreign patents, ranging from self-starting devic-

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National Association of Broadcasters 2015 Convention Report by Richard Majestic It’s too bad broadcasters haven’t realized that their days are numbered if they don’t find new and compelling content and the power of the internet; they will go the way of the horse and bug-gy. I attended many panel discussions hosted by young creative kids who are developing bril-liant content, new distribution methods and brands that are the future of media for the masses.

(Continued on page Five)

the National NC-2-40D communications receiver story starts on page 3

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The NMRCC Meeting Minutes by Chuck Burch NMRCC 2015 MEETINGS

May 17th – Spring Picnic and Tail-gate Event

Jun 14th—Reflex and regenerative radios

Jul 12th - Radios with tuning indica-tors (magic eyes, shadow tun-ing, tuning meters, etc.)

Aug 9th - Unique and novel radio antennas and noise eliminators Sep 13th - Wild Card Sun-

day” (nifty science gizmos, novel science toys, or non- radio collection, electronics, or science related that you think will dazzle your fellow members

Oct 11th – Fall Picnic Audio dis-tortion of radio receivers demo

Nov 8th - Old computers, calcula-tors, slide rules, and associated items

Dec 13th - Unusual Devices/Stump the Experts- Unusual tubes, light bulbs, transistors, and ra-dio parts. Also, who can identify that strange gizmo you found, or explain how an unusual ob-ject works?

Proposed Programs *Radio trouble shooting and repair workshop *Alignment of AM/FM tuners work-shop

NMRCC April 12, 2015 Meeting Minutes

The tailgate auction had several nice radios and other items.

The meeting was started at 2:15 by vice president John Estock. A potential new member visited and introduced himself: Bob Riola restores antique furniture and uses old wood to make furniture. He has several radios that he is interested in getting to work. Plans for the spring picnic were dis-cussed. It was decided to have it at Quelab, our new meeting location. Various members volunteered to bring items for the picnic: Ron Monty: drinks and ice, Don Menning: pizza, John Estock: chicken, David Patterson: dessert, and Ray Trujillo: paper plates and flatware. Club members are wel-comed to bring other potluck items to share, and since drinking alcohol in moderation is allowed at Quelab, bringing booze is permitted. As usual, members are encouraged to bring do-nation items for the auction to help offset the cost of the picnic. Les Davidson brought in the bad 100 Megohm resistor he discussed last month. It is not very often you see a resistor with a violet multiplier color band. He also showed a What-Is-It.

One of the Quelab members correctly identified it as a Rongeur which is a medical instrument

with a sharp-edged, scoop-shaped tip that is used for gouging out bone. The monthly theme was 1930s art deco radios, chrome chassis and intricate wood design radios. Chuck Burch showed a Detrola model 568-1 radio that has a dark-green leatherette cov-

ered cabinet and a chrome-plated front panel. A version of the radio appeared on the cover of the book Radios Redux by Philip Collins.

Mark Toppo showed a beautiful prototype wooden table radio manufac-tured in Los Angeles probably by Jack-son Bell. It was in very poor condition

when he got it, and it took him three years off-and-on to restore it. It has the original grille cloth and plays. He also showed a nice red Radio-Glo radio.

When he got it, it had broken glass. Mark found a 100 year old glass shop that had a large inventory of vintage glass, but they suggested it would be more economical if they search for a match to Mark’s glass when looking through their inventory to find a match for high-paying customers. After a year, they contacted Mark saying they found a decent match. The end result was a very nice radio. Don Menning showed a vintage clamp meter and a kid’s Bausch & Lomb microscope. Marks’s radios were voted as Best of Show. The meeting adjourned at 3:00. ~C.Burch

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When you lift the NC-2-40D receiver you know where the term Boat Anchor came from, it’s not that big but must weigh 60 lbs. A quick look at the schemat-ic; it’s a simple 12-tube super-heterodyne radio with an ampli-fied AGC, a noise clipper, a BFO, push-pull 6V6 audio out-put and choke input power sup-ply, but then you look at the RF coil assembly, it’s housed in cast aluminum catacomb that moves horizontally at the bottom of the chassis with a rack drive gear drive and contains the local os-cillator coils, RF amplifier plate tanks and the RF amplifier an-tenna tanks. These coils are in three separate compartments, front to back. However, there are six bands and six sets of three each of these coils in their little compartments with variable capacitors. This beast covers 0.490 MHz. to 30.8 MHz. and the dial is precisely marked and the radio can be aligned to hit every one of those marks every time. It was my experi-ence, after the rebuilding that this radio didn’t drift off frequency at all, even though there was no temperature compen-sation in the separate local oscillator cir-cuit, the coils were wound on bobbins that kept them stable over a wide temperature range. The tuning capacitor plates are shaped to provide an almost linear tuning scale. The RF amplifier is the simple tuned grid or tuned antenna input that has a Faraday shielded balanced antenna input winding that keeps, out of band noise out of the RF amplifier. The RF amplifier plate is also tuned and coupled coil connected to the mixer grid. The NC-2-40D uses the elec-tron coupled local oscillator pentagrid mix-er.

The radio uses two IF amplifiers, the first transformer being the standard dual tuned 455kHz. Type. The second IF transformer has selectable “Q” positions and at its nar-rowest a 455kHz. Crystal is in the circuit, this reduces the IF bandwidth to about 3.2kHz. and the widest is 12kHz. The au-dio bandwidth is then from 1.6kHz. to 6kHz. The 2nd detector is a diode type us-ing the grid and cathode of a dual triode.

A 6SJ7 pentode is used as the amplified AGC. Another triode is the first audio am-plifier (AF) and noise limiter. Negative noise pulses cuts off the grid and positive noise is clipped by grid current. Another

dual triode is the audio phase invertor that then drives the two 6V6 push-pull output tubes. The detector and audio design is

very HiFi quality and when a good output transformer is used this radio sounds great. A 6SJ7 pentode is the BFO and it’s cou-pled into the 1st IF transformer. It’s a varia-ble frequency BFO so it can be used on CW and sideband.

The power supply is the basic 5Y3G full wave choke input filter with negative end floating to provide a negative VDC for bias use. The companion speaker has a 10” PM speaker with the output transformer and retains the Deco design elements of the radio even though this radio was sold in 1946 through 1949. It’s my assumption that this radio was designed in the mid-‘30s because it uses tubes that were intro-duced in 1934.

Performance Measurements

The sensitivity was truly amazing, all but the 14MHz. to 30MHz. band had 0.3uV sensitivity with 20dB S/N and it didn’t vary from one end of the dial to the other. Highest frequency band dropped to 0.7uV sensitivity with 15dB S/N, which is still very usable, tube noise was mostly what reduced the S/N. Note: these measure-ments were with the NC-2-40D at max RF gain, AGC on and using my HP 606A RF generator.

The Restoration No offence intended, but this radio was a mess. It had been owned by a ham who modified every circuit to make the radio work and totally missed what caused the radio to stop working properly in the first place. In replacing out of 5% tolerance resistors I measured the screen resistor for

the second IF at 1Meg and it was supposed to be a 68K resistor, this caused the radio to loose sensitivity. It also caused the BFO

not to have the correct levels so he modified the BFO circuit. Almost every resistor was way out of tolerance and had to be changed. I use metal film resis-tors and metalized Mylar ca-pacitors. I replaced all capaci-tors and the three power supply electrolytics. The large mica looking capacitors were also replaced, they are really paper foil capacitors. The 2nd detector audio output jack had been replaced with a switch because the BFO switch had failed; I put the jack back

in the front panel. I was able to get the shaft driven toggle switches to work too. The antenna input circuit is a balanced 300 Ohm design with a Faraday shield around the coupling windings, it’s not a low im-pedance unbalanced input, but the previous owner cobbled a PL259 jack onto the an-tenna input terminals, which unbalanced the antenna circuit and destroyed the noise rejection design. I restored the antenna terminals as designed. Back when this ra-dio was designed most hams and radio listeners had long wire dipole antennas that were connected with 300 Ohm open twin lead.

The Alignment

The IF alignment is done with the band-width switch in the narrow position but not with the crystal filter in and the IF aligned to 455 kHz. The procedure is to switch in the 455 kHz. Crystal and rock the RF gen-erator while watching the AGC voltage for a double peak, the crystal in this radio was right on 455 kHz. The next step is to align the local oscillator at two points at each end of each band us-ing the trimmer capacitor at the high end and adjusting the padder capacitor at the low end of each band, then recheck the dial accuracy at multiple points on each band. Then at the mid-band of each band peak the RF plate and antenna trimmer capaci-tors. I also check to see that the high and low end of the each band has the same peaks, if not a coil may be shorted or modi-fied. Fortunately all bands were perfect, not modified. Next step is let the radio cool down and check all bands for frequency accuracy and

The National NC-2-40D Communications Receiver by Richard Majestic

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es for automobiles to his new invention that centered around the idea of using ra-dio to transmit photographic images. According to Wikipedia, “Jenkins also published an article on ‘Motion Pictures by Wireless’ in 1913, but it was not until 1923 that he transmitted moving silhouette images for witnesses, and it was June 13, 1925 that he publicly demonstrated syn-chronized transmission of pictures and sound, which he was granted a patent for.”

My July 1924 Motion Picture Classic magazine article seems to be an early ex-ample of Mr. Jenkins’ rolling out his pub-lic relations efforts on the synchronized transmission of pictures and sound which he was still testing at the time.

“In 1928, the Jenkins Television Corpora-tion opened the first television broadcast-ing station in the U.S., named W3XK, which went on air on July 2. Signals were first sent from the Jenkins Labs in Wash-ington, five nights a week. At first, the station could only send silhouette images due to its narrow bandwidth, but that was soon rectified and real black-and-white images were transmitted,” according to the Jenkins Wikipedia listing.

It’s worth noting here that Jenkins Televi-sion Corporation was liquidated four years after this story appeared in Motion Picture Classic Magazine, and the company’s as-sets were acquired by none other than Lee DeForest, the self-proclaimed father of radio. Ironically Dr. Lee DeForest is quoted in the Motion Picture Classic story on Jen-kins television invention saying, “It will be at least twenty years before radio-movies in the home will be perfected and there is no certainty that 1950 will see such perfec-tion.” Within months, of the DeForest acquisi-tion of the Jenkins Television Corporation, he went bankrupt and all his assets were bought by David Sarnoff’s RCA Corpora-tion in order to stop all work on electrome-chanical television. At the time of the RCA acquisition, Jen-kins’ electromechanical television technol-ogy was already being overtaken by elec-tronic television under development by Vladimir Zworykin and Philo Farnsworth.

This is an interesting chapter in the history of the invention of television and the start of broadcasting with moving pictures. ~D. Wilson

Radio Movies: Will radio and the motion picture combine? By David Wilson

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The two NAB shows in the old Hilton ball-room was the most surprising and advanced of all, 4K video and great audio; maybe the NAB is awake to reality. Technically 4K video is here, the ‘head in the sand’ engineering stand-ards guys have not developed or even pro-posed an over-the-air (OTA) standard, two, possible three OTA systems have been pro-posed but only one tested OTA by Sinclair. I have watched a 4K Netflix movie on my 28”

4K monitor, off the internet on a 25Mbps cable ISP and it was amaz-ing quality and no buffering. One group has ignored the antiquat-ed media delivery systems and al-ready turned it into a money making business; Netflix, Amazon Prime, AppleTV, Hulu, HBO, CBS, You Tube and many more. They are de-veloping original programming that’s so good it’s creating a large group of ‘cable cutters’, those who are not interested reality TV like the Kardashian or the local tabloid news. The internet youngster’s have been working on new content and how to develop a brand for their new con-tent. This area of media content is

going to be a major factor causing more people to be-come ‘cable cutters’. An ex-

ample you can watch today live is http://twit.tv/ , watch Saturdays at noon MDST. Last year Cannon and Red led the way to selling 4K cameras that were low priced when compared to televi-sion cameras sold just a few years ago. This year, Cannon, Red and now Black Magic showed 4K, 6K and 8K cameras with wide dynamic range, called HDR which increases the black to white dynamic range to the equivalent of 14 bit from the 8 bit we have gotten used to with HD television. The improvement is re-markable and major improvement. All but gone this year was the trans-mitter manufacturers, all of them would have fit in the Quelab meeting room. They have been replaced on the LV Convention Center floor with drones, camera support gear, lens, new editing software and media con-tent suppliers. This year at NAB 2015 was exciting and very well attended with over

103,000 registered attendees and all LVCC floor space occupied, over 1,000,000 SF, this was an-other first for the NAB. ~R. Majestic

NAB 2015 Report

See the whole NC-2-40D Story on page 3

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then again after a few hours check each band for accuracy again.

Final Checkout I usually run each radio I restore a few days to make sure nothing is going to fail, like a tube or component, I did a full week’s test and found no problems. The audio quality from this radio is very good and is a pleasure to listen to, the AVC (AGC) is very good, it’s almost impossible to overload the RF stage, so the audio dis-tortion is very low even though the radio has exceptional sensitivity. If you find a NC-2-20D that is in good cosmetic condition don’t hesitate to buy it, but knowing that almost every tube, capac-itor and resistor will have to be replaced. Component quality in the late ‘40s was very bad no matter who made the radio. ~R. Majestic Special thanks to Tony Levitino the owner

of the NC-2-40D reported on here

The National NC-2-40D Communications Receiver by Richard Majestic

Above, I had just started to replace the capacitors when I dis-covered all the bad resistors and extensive modification, to the right is the finished restoration. To the bottom right is the other side under side view with the rectifier, power supple filters and 6V6 pair audio output tubes.

Above is the RF coil assembly in the mid-position covering about half of each under chassis circuit wiring and components.

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The New Mexico Radio Collectors Club is a non-profit organization founded in 1994 in order to enhance the enjoyment of collecting and preservation of radios for all its members.

NMRCC meets the second Sunday of the month at The Quelab at 680 Haines Ave NW , Albuquerque NM Tailgate sale at 1:00PM meetings start at 2:00 pm. Visitors Always Welcomed.

NMRCC NEWSLETTER

THIS PUBLICATION IS THE MONTHLY NEWSLETTER OF THE NEW

MEXICO RADIO COLLECTORS CLUB. INPUT FROM ALL MEMBERS ARE SOLICITED AND WELCOME ON 20TH OF THE PRECEDING

MONTH. RICHARD MAJESTIC PRO-TEMP NEWSLETTER EDITOR, SEND ALL SUBMISSIONS IN WORD FORMAT, PICTURES IN *.JPG

FORMAT TO: RMAJESTIC@MSN.COM

N E W M E X I C O R A D I O

C O L L E C T O R S C L U B

New Mexico Radio Collectors Club Richard Majestic (Membership inquiries)

5460 Superstition Drive Las Cruces NM 88011

E-Mail: ronmonty@comcast.net Phone: 505 281-5067

E-Mail: rmajestic@msn.com Phone: 575 521-0018

FOR INFORMATION CHECK THE INTERNET

http://www.newmexicoradiocollectorsclub.com/

USPS Stamp

NMRCC Officers for 2015

John Anthes: President

John Estock: Vice President

Richard Majestic: Treasurer

Chuck Burch: Secretary

Ron Monty: Membership

Mark Toppo: Director

Ed Brady: Director

Ray Trujillo: Director

John Hannahs

Richard Majestic: Newsletter Editor (President pro-tem)

REQUEST I want to create a club history column, a story about why we collect old radios, old

ham receivers and transmitters, vacuum tubes and old black and white televisions.

What’s the motivation? What’s the limits we set? Why a particular brand? Why a

particular year? Are we collectors or technology hoarders? How much time do we

spend on this hobby? Do we research and record the history of items we collect?

What are our sources of the items? What are the stories you’ve heard from a seller?

How far will travel to get an item? What’s your hot pursuits today?

Put your story in words, write it up and I want to print it as a monthly column in our

newsletter. ~RM