1

EDGES MEMO #300 MASSACHUSETTS INSTITUTE OF TECHNOLOGY

HAYSTACK OBSERVATORY WESTFORD, MASSACHUSETTS 01886

August 28, 2019 Telephone: 617-715-5571 Fax: 617-715-0590 To: EDGES Group

From: Alan E.E. Rogers

Subject: Details of EDGES-3 prototype

The concept of placing all the electronics in the antenna was proposed in memo 289. An update to the design, in which the number switches in reduced, is described in memo 293. Simulations of the EDGES-3 beam chromaticity are given in memo 294 and in memo 298 with a wire grid ground plane. Following early tests of the initial EDGES-3 prototype it was discovered that RFI generated by the Nuvo PC, DC to DC converters and other switching electronics was strong enough to require an additional layer of shielding and filtering as described in memo 299.

This memo gives details of the revised design based on separating the electronics with fast switching waveforms into a separate “inner” box. The analog “backend” electronics is also contained in the box to provide additional isolation to prevent feedback of the amplified sky signal into the antenna. A block diagram is given in Figure 1a along with a photo in Figure 1b. The VNA and its DC/DC converter is outside the inter shielded box because the spectrometer is not run when the S111 measurements are made with the VNA.

Figure 2 shows the overall circuit diagram of EDGES-3. The ethernet connections to the outside and to the VNA are made using fiber. A cable connection to the outside can be made for charging the batteries. This connection is made, which the EDGES -3 is not running, via a cable which passes through the pipes which connect the antenna boxes shown in Figure 12.

Register

100 temperature Frontend box 101 temperature Ambient load 102 temperature Hot load 103 temperature PR59 in inner box 106 Output % Thermal control 150 Voltage Battery 152 Current PR59 current

Table 1 Some key parameters monitored.

Table 1 lists the key registers which can be read out for monitoring purposes vis the RS232 link from the Nuvo PC to the PR59 thermal controller. When S11 measurements are needed the VNA can be powered up using the MEZIO control and after a delay for the VNA to reach a stable temperature the control and data retrieval is performed using the Ethernet link to the VNA.

Figure 3 shows the mechanical details of the frontend. The left box contains a 10 ft long cable with a switch which provides and “open” or a “short”. The middle box contains a 50 ohm load which is heated by a 75 ohm resistor and filled with Aerogel Silia Gel Lumira LA100 for insulation. Figures 4, 5 and 6 show the circuits of the LNA, noise source, and “out of band” noise.

2

Figure 7 shows the circuit of the “switch board” which converts the MEZIO “pulldown” outputs to “pullup” outputs to control the R.F. switches. Figure 8 shows the circuit details of the inner box and Figure 9 shows the mechanical details.

Figure 10 shows the layout of the outer box and Figure 11 gives the dimensions of the antenna box. Figures 13 give the dimensions of the antenna base.

Items Conditions Volts Amps W

Frontend 12 0.8 10 Frontend + PC Idle 13 1.9 25 Frontend + PC Fastspec running 13 5.5 72 Thermal Max 13 2.0 26 VNA Only 14 VNA + PC + thermal Min 39 All Min in spectra 72 All Max in spectra 98

Table 2. Power consumption for different items and conditions.

Table 2 gives the level of power consumption for parts of the system and different modes of operation. Theoretical models show that 98 watts, should only result in a 5 deg C temperature rise, via combination of the radiation and convection. A test was made in which a 75 W lamp and a 20 W fan were placed in an antenna box resulted in a 10 deg C temperature rise. This test was made before applying goldstone paint that increases the IR emittance. A test of placing the antenna box in the Sun resulted in a rapid rise of the 10 deg C. More tests are underway to ensure that thermal control, at least under conditions at night in Oregon. Operation during day may require circulating air through the antenna box via plastic pipe to heat exchange box in the under the antenna or a control hut as in EDGES-2. For initial operations in Oregon the wires for charging the batteries shown in the circuit of Figure 2 will only be connected via the lower box in Figure 12 during periods when the spectrometer or VNA are not running so any RFI from the charging source or cable is avoided.

3

Figure 1a. Block diagram of EDGES-3.

I

connection between antenna box panels

reflection measurement reference plane at input of receiver

RIGHT-HAND BOX

frontend box

to backend

1S11JTCH CONTROL

1 to Vector Network Analyzer

8 position input switch

Thermoelectric Elements Batteries

~----1Vector Network Analyzer

Inner shielded box for all switching electronics DC DC converter battery charging control

all connections to box are filtere L __________ J--~-.DC charge t t Ethernet

ion 1------------~spec rome er fiber 14 bit ADC PCie PC

'-----+.iSwitch and thermal control 400 Ms/ s ethernet

4

Figure 1b. Electronics with inner box cover removed.

5

Figure 2. Overall circuit diagram

antenna

short

open

load T2

hot

Power Amps + switches 5w hot 3w pin

VNASWind Q Q VNA sw5 3 5 9-pin colors

1 irey NUVO 25w idle 72w fastspec thermal 10w All max ~96w O O VNA s11'9 9

op/sh gndo o short sw10 3 l nolse+l2v sw12 O O open sw11 2 6

2 orange 3 black 4 red

Hot load resistor 74 ob.ma 3 !SW 3.6w Fan 1.92w

sw3

s11'2

input ref. plane

MSP8T-12D+ 125 ma/contact

sw pos wires 1 orange 2 white 3 red 4 purple 5 11rey 6 yellow 140 ma 7 blue CCR-33S80 8 green LNASW

swfl

.we s11'9

LNASW gndO O I.NA swfl 3 B LNA +Bv O O I.NA s11'9 7 9

obnoise+12VQ o ainp +12v 4 4

5000pf 4-40 feed-thru 9900-381-6004 or 6008

5 green 6 purple 7 brown 8 blue 9 yellow

12T Ulma +batt _'J gnd -6,

603-1015-ND Fan in inner box OUT OF BAND

NOISE

120 ma TC-NTC-1 ZXB0-6013E

LNA + amp 22dB

+12v h1

l0dB

inside

... 14dB4dB BdB

I thermalbox

Software PC Llnux Nuvo 32C idle 43C fastspec

Thermal RS232 Llnux also monitors temps (100,101,102,104) and voltage(150)

DC /DC PC pr59 backend ISW in inner box Fieldfox - w/o int . batt 2w idle 14w running

Need lOOOwh 12h 6 Li batt Transition M/GE- ISW 10/ 100/1000Base-T to l000Base-Sx/LX 12 - 24v 1.2 watts laird 28 ferrite cores inside and out side inner box where possible Genasun internal processor dra"WB 0.1 amps

K&I. 7LL30-190-T600-0/0

ZKL-1R5 Signatec PX144OOA

14 bit ADC

400 Ms / s

40dB VLF-225 PC!e

~ ~:~:t°~o:~x USB0 T3 hot load NTC-2 USBl

wires trom solar panel

H fiber to VNA

+12v elhernet fiber

+12

NUVO 7002DE

PC

noise

sw12

cable

CCR-33S80 VNASW

sw5

VNA N9923a

255-1589-ND x 16

sw10 +15v +12v 3,~4

Sll'X

~-~-~ 1 To 010.1 2k,!; · <> n ot f0 open

short

sw11 PYB30-Q24-S15-U

used fl DOx from Mez!O pins 1,35,3,37,5,39,7,41 ll,45,13,47,15 ,49,17,51

h0

bl

Tl pin9 T2 T3 TC-NTC-1 DOO

T4

D015 pin42

RS232

DC-DC conv PYB15-Q24-S12-U

fiber to laptop

External charger via

DC power lines cable CCR-33S80

3:!ii switch control pull swO t.hru sw15 down aw 13,14 spare

497-2949-ti-ND carry + and -(,mdl +12v~ +Bv Tusonix 4251-00"4!,11 ~--------~

1i 1i from inner box EXTERNAL PWR 14 - 20v ,!,0.33 ,.0.1

8v to I.NA not implemen t ed EDGES-3

SPECTROMETER aeer 14aug19

6

Figure 3. Frontend box layout.

-

Feed-1.hru 0.8 from a down spac api 9900-

filters ide 0.5 ed 0.25 881-6006

0.4 down oulput is and 0.55 fro m edge

w5o o vna1nr a

NC vns ,,.goo .,,.g O 0 ll]ld ohorts

co.1+12 swl

gnd lnasw8

+av lnasri

+12v +12

2 0 0 00 00

V O 0 00 8 dB

_J

0

0.125 hole 0.3 from edge

0 0.25 hole In center down 0.3'"

brackets for MSPBT with 0.2" diam holes width = 0 .5"

0.125"

~ppedl 1/4i2: Fl I 0 5" " . I .. o.5 0.22

holes for MSPBT mount are 1.8" apart 3.3" from back and 0. 25 from front hole for connector 1.6" diam 1.1 from bottom 1.1 from front

outer box 1550J 10.38x6 .89x2.62 sits on thermal elements 1.07" off bottom plate

1590WY LONG CABLE CUI

2.125 1.26"square 6 .5x3.125

□ HOT LOAD

11 Fainiew ST1852F Timeslticrowave 8102 - 141 /421n / 2645 / 26001 68999 088 2SMRC 8/ N:0001

switch inside box 3. 62x3. 62x1. 654

ow10 sw'.11 LL 141-9SMR SW2

LNA

rl SHP-50 HPF ~ 1550B 4. 51x2. 52xl.19 sw5 nr9 ~

159 OLLBF 2x~ xl.1 l lOdB

141-4SIIR 3dB

~ In box

rtee ~~

ut of band noise

output to backend

5"01234567 ' ' ' ... '

MSPBT

~ ..., ~ .c

_g L cd "' 0

r, r,r,

P" !"r 26dBO Cl)

"' - w12·O i:: ~n n r1

~ Wl

Sw8 Sri

oW-JS~Mfrom bottom 1. 42 from front to VNA

center

2"90deg to ant

of antenna

□ J4 0.8 "

c:;======:::::;::::::::: 0 .125 therm elemen 1.07"

tenna an 0.5 0.8

hole 3. 5 from side from bottom

DO connectiom from MEZIO 0 12 34 567 8 9101112131415

5 3 37 5 39 7 41 11 45 13 47 15 49 17 51 1 3 sir from aw board to MEZIO 0 53 G

1 2 3 4 5 6 7 8 9 10 II 12 13 14 15 54 55 58 57 58 59 60 61 27 63 29 65 31 67 33

ND +12v 9 2 1 9 20 21 22 23 24 25 26 28 30 32 34

FRONT-END parts in tempera t ure controlled box

7

Figure 4. LNA Circuit

2.2 uH 587-2899-1-ND 0603 27 ohm A1013186CT- ND 0805 1.0 K Pl.OK DECT-ND 0402 75 nH 445-6317-1-ND 0402 270 nH PCD-1054CT-ND 1008 470 nH PCD-1057CT-ND 1008 Minicircuits SAV-541+ in an alternate for ATF-54143

Amidon FT-82A-43

2.2 uH 0603

HSMS-2822

1008

0402 1000 75nH

ATF-54143 2.5v

BOma

10uH +12V

LM340-MP-5.0

2.2

1008 270nH

1.0

+5v

7 0.01 ERA-1SM+

0805 270nH

30 lk 0805

390pF

1~

390pF

2.2 uH 0603

0.017

0603

Gain 22 dB

150 0603

40ma

Gain 13 dB

EDGES-3_LNA

AEER 15d.ecl8

LNA out

8

Figure 5. Noise source

26 dB

,-11000pf

small board on SMA flange

3k

lk 90

7 1

100 NTC

)--------, f-----f--------. ~~~ .~~ 12v NOISE 10uH I

Noisecom NC302L

7 0.03

NTC 100 ohms

7 0.023 __ _J

at 25C RL2003-62.4-73-k GE Sensing Type Rl20 beta = 3468

EDGES-3 Noise Source

aeer 15dec18

9

Figure 6. Out of band noise source.

Notes: Level adjustment via noise diode current. Reduce 1k to decrease reduce 100 to increase

+10v Rl

Cl

470 pf

4.7 pf

1.5k

6

+5

510

0.01 C3 40 dB

200

0.1

1k

Noisecom NC302L •

◊ AD8011AR

C9

adjusted for out of band noise level

R7

150

0.1

RB

I

2.2 uH

~15ma +12

1

U3 LM340

2. 2 :::r:: Cll V

LM2937IMP-10CT- ND

3 +10

2.2

7 C12

20 MHz low pass filter

Notes : Noise added to reduce signal power on cal. to ~ 4%

m,y-y'\._____. _ _J 3 video out R2

51 0.01 ~ C5 68pfJ

+5 R9

5.1k 5.lk R13

U2

12 R5

T 0.1 '¢7 C4

4.7pf

AD8011AR 32 dB

C7

EDGES-3 out of band

noise source AEER 1feb19

10

Figure 7. Switch board circuit

255-1569- ND

+12v

rYv'\ 2k A B

DO swo 2 3

D 2k

Dl SWl 2 3

2k D15 SW15

1 2 3

A = normally a short but could be open B short or a 2. 2 uH inductor 587-2899 EDGES-3

C = open or 0. 01 uF switch board

D - normally diode 641-1002-1-ND or open aeer 14jan19

11

Figure 8. Circuit of electronics in inner box

Output 0 1 2 3 4 5 6 7 B 9 10 11 12 13 14 15 Mezio pins 1 35 3 37 5 39 7 41 11 45 13 47 15 49 17 51

Tl T2 T3 9 +12~ 2 gnd

PR59 68

CUI pwr pin Mezio

rs232 gn +bb - +

ethernet NUVO

pwr-up pwr

GE-ISW gn +bb pwr-up•

VNA fiber

NUC fiber

+12~ DC/DC 10VR1

Genasun +bat• g12

10VR1 gb gb

gc gc charge•

• internal side of filter-feed-thru

0 0 0 0 03 4 0 0 0 07 BOO O 011

12 o o o 015 switch

000 000

Tl T2 T3 0 o+

CUI elements

backend input SMA 0

gnd 0 ONUC pwr-up

0 0 +12v

0 0 +bat

0 0 +charge

0 0 0 0

Fan 603-1015-ND 15. B cfm 1. 92w heat Bw/K

10VR1 0.01 ohms/leg feed- thrus ~ 0 ohms gn is grounded to Nuvo chassis g12 is connected to box

0 1 1 35 2 3 3 37 4 5 5 39 6 7 7 41 B 11 9 45 10 13 11 47 12 15 13 49 14 17 15 51

Brn/Red Red / Brn Gm/Red Red Grn Gry/Red Red/Gry Ora / Pik Pik/Ora Brn/Yel Yel/Brn Grn / Yel Yel/Grn Gry / Yel Yel/Gry Ora / Pur Pur / Ora

+ 12 9 Blu / Pik gnd 2 Ora / Red

0 Laird 28 ferrite cores Genasun charger no t used when external charger is used. The genasun draws 0.1 amp when no charge voltage present

NUC fiber

VNA fiber

INNER BOX CONNECTIONS

aeer 14aug19

12

Figure 9. Inner box layout

r dimensions Box oule

11.6x sides are top and

16.6x4.6 0.25 thick

bottom 0 .125 thick

□ 3.0"' from bottom ofllideptlD91

I RR59

I

BACKEND PR59 5.25x2x1.75

NUVO 9.5x9x4.35

POWER 9x4.5xl.5

I 10VR1

I I 10VR1

I

I fiber converter I

□ I fiber converter I

-

1

Fan 603-1016-ND 16.8 cfm 1.92w heat Bw/K

0000 0000 0000 0000 switch

000 000

temp probes 0 o+

CUI elements

backend input SMA 0

gnd 0 ONUC pwr-up

0 0 +12v

0 0 +batt

0 0 +charge

0 0 0 0

Fan air into box this end

NUC fiber

VNA fiber

INNER BOX

aeer 29apr19

13

Figure 10. Outer box layout

I

37.5"

32"

26. 3"

20.75 4 2.5x6 x3.75" high batteries in parallel □

switch

W board

P59 II

backend 4x6 .5

2x5 .25 6x12

Nuvo

9.5x9x4.35

POWER

11. 5x16 . 5x4. 5

~ D

~

r r--------------------------;-7

RECEIVER FRONTEND

11x7 '-fJlxfl ____________________ J I

Ioa-m msu1fti'6:li 9x1-Z.ox0:-75 __ J

+ 2 11.5x4xl + 9x4x1 + 7x3x0 . 75 + 2 2x4. 5x0. 75

VNA

12x8

_TI 1. 6"

Box layout

aeer 22aug19

14

Figure 11. Outer box dimensions.

separation of fiberglass supports=32" 34 _5• between centers

EDGES- 3 Box aeer 3jul19

37.5"

26.3"

o side plate 4. 7" x 26. 3" 0

0.75"diamSeparation=2Q. 75" hole for plastic rod attachment of support side plate 4. 7" x 18.l''

side plate 0. 25" thick 4. 7" high 37" long,:.__ ____ _

0

RECEIVER FRONTEND

1" diam hole for fiber and power

sid e plat e 4. 7" x 18. 1''

Top and Bottom plates 0.125" thick

side plate 4. 7" x 26 .3"

7.75"

side plate __/4.7" X 1.1"

15

Figure 12. Connections between antenna boxes.

Receiver Box

lotted 1" x 2" hole in base s 0

of

3/4" ad

f box for gap adjustment

1''

apter -- II base

Hammond 1590G

cover

1- 14 thin brass nuts 92174A675

I I

cover

1.5" pee ted ex

0 .5" -

I I I I

2.0"

ase

1705'1'32 1" cut to 13.5" long with 1-14 thread 1.5" 1 ong on each end

92174A675 1-14 nuts cut

7513K18 3 / 4 " adapter + 7

Qty

down to 3/ 8 thick

513K242 lock nut

2 pipes 7 nuts cut down to 3/ 8 t hick 2 boxes with slotted holes in base

e 1 box with 2 holes in bas

I I

~ 1"

Connection of box to pipes

aeer 27jun19

16

Figure 13. Antenna base.

I 32"

□--------□□--------□

I '----- 20.75• __ ____, f-D I I ~ 7.75" I I I I I 1 NOT TO SCALE 32

.. 11

I I I I I I □--------□□--------□

,- -- - -8.0"

- - ~ : -2

0.5' 4.0"

7.5"

: --, . _L"--. 2.5"

0 wheels

-: r: ! . . 38x62x0. 75" plywood base in field

2.5x2 .5 outer dimension fiberglass 6548K71 3/ 4-10 threaded rod USplastic PVCTR340 or 98831A730 black

EDGES- 3 Base initia l protot ype with wheels

aeer 16aug19

17

Figure 14.

Receiver Box

female sma on receiver box

plastic rain cover

soldered into hole

~1. 6"

male sma flange connector

Antenna Box

1/2" - 13 93025A297 2" long

9217 4A435 1/2" - 13 nuts

brass rod with hole into which coax center conductor is soldered 0. 5" diam 1/2" -13 threaded end allows some adjustment of box separa lion

Connection of receiver to antenna

aeer 3jul19

18

BT sw 125 ma LNA 120

Genasun draws 0.1 amp without when not charging external 15 amp charger used with 4 batteries in parallel

2499-003-X5W0-1032LF or

Hot 160 backend 195 CCR 140

Tusonix 4251-004LF EMI filter feed-thru 75dB at 100 MHz

10VR1

.----------------------------, 60 dB at 30MHz

10VR1

PYB15-Q24-S12-U DC - DC converter

15w

Genasun GV10 lithium GV-10-Li-14 .2v 12v LIFeP04( 4S) /10. 5A

needs> 9v 140w

Notes: Nuvo 25w idle 72w running fastspec electronics + switches + hot 5w Thermal 10 - 60w Battery voltage ~ 13v charged

charge

+ + 12v to electronics 10w

to 12v + K2B12v10EB

several 10amph batteries in parallel for 120wh

+ to VNA

+

DC/ DC converter 2-15w

to Nuvo PC 30-70w needs> Bv

+ to thermal controller 10-60w

+ optional charger

power from external source needs to be > 14v

Ferrite cores on cables

EDGES-3 power system

aeer 14aui:(19

19

Figure 15. Power system connections.

sw,o

D11 SW11

SW12

SW13

D14 sw, ..

D15 SW15

• • EDGES 3 SWITCH BOARD

SILKSCREEN

20

Figure 16.

battery

battery

PR59

Nuvo

cntl from SW board

VNA DC/DC

11

battery I

battery f _charge"

I

backend

12v

bat charge

to 8-pos SW

16pin W board

to switches

2pin f--~====:._T~C~ probes

2pin RECEIVER FRONTEND

2pin ~----------~ 12v to SW board

12v to HOT load to batteries

charge

,;:::============:::;--,+15v

ethernet ISW fiber

+15v VNA

from to #pins MezlO SW board 16 PR59 TCprobes 3x2 PR59 thermal 2 SW board 8-pos 9 SW board 2-pos 9 12v SW board 2 12v hot load 2 bat batteries 2 bat VNA DC/ DC 2 SWb DC/ DC cntr l 2

Fiber parts L-com FOA-001A Transition M/ GE- ISW SFP-01

Who Laird t28 ferrite cores

en ex ernal charger is used internal Genasun is not used

Connections using connectors

aeer 14aug19

21

Figure 17. Connections using connectors

Figure 18.

RECEIVER BOX -[ c,----,---------_____:::;~~ ~-U

GROUND

I

I

I

~

EMPTY BOX

~ - - - - - -~- _c______.__ - - - - - '--

DIAGRAM OF EDGES- 3 FIBER and CABLE PATH

22

Figure 19. Battery charging.

4 K2B12V10EB Lithium Iron Batteries + + + + #14awg

Fuse

Ran test 14 Aug 16. Currents: Only Front-end hot-load off + temp controller

running but not controlling temp: 1.2 amps added PC on: 4. 5 amps

added fastspec 1-tap: 7.5 amp 3-taps: 11.2 amps

Batteries ran for 39 amphrs Went down from 13.16 - 12.00v slowly

12.00 - 10.60v in a few minutes pr59 controller LED went red at 10v - seen thru fan vent Batteries' internal PCM opening so batt voltage going to zero Started lOamp re- charge voltage went

12.00 - 13.6v in one hour and charge completed in 4 hours

+ Batt+

Inner box

Batt-

Charge +

EDGES-3 batteries + charge connection

12aug19

23

Figure 20. Assembly instructions.

1] Assemble base with washers and nuts under the plywood and horizontal fiberglass sections tightened

2~ Add antenna and receiver box without top covers 3 feed fiber from inner box down through hole and unattached pipes 4 Adjust antenna and receiver box separation so that pipe assembly

6 Check that box separation is about 1. 5"

can be attached with screws from below 5l Add washers and nuts and tighten

7 Carefully add SMA connection between antenna and receiver box 8 Connect Laptop via fibers using ST connectors 9] Put cover on antenna box and connect battery for no cover test" 10] Put cover on receiver box -watch temp should be OK to run 30m 11] remove receiver box cover - to change battery

antenna box receiver box washer + nut ..___

Laptop

-: -

Nuvo

lm ST fiber pair

top of pipe

pipe

bottom of pipe

ST conne ctor

15m ST fiber

·-1r EDGES-3 Assembly

-'

: . C_) wheels washer + nut _...

-

I

,

l . .

u

initial prototype with wheels for test at West Forks Maine

aeer 22jul19