NATIONAL RADIO ASTRONOMY OBSERVATORY

CHARLOTTESVILLE) VIRGINIA

ELECTRONICS DIVISION INTERNAL REPORT No. 220

ULTRA LOW-NOISE, 1.24.7 GHz

COOLED GASFET AMPLIFIERS

S. WEINREB

D. FENSTERMACHER

R. HARRIS

SEPTEMBER 1981

NUMBER OF COPIES: 150

ULTRA LOW-NOISE, 1.2 - 1.7 GHz

COOLED GASFET AMPLIFIER

Table of Contents

I. Introduction . • • • • • • • • • • • • • • • • . 3II. Design• . . . • • •

• • • • • • • • .Construction . • • • • • • • • • • • • • • • • • • • • • • • • • •

. . liIII. ConstrIV. Tuning

. * * . . 17. . . . • • • • • • • • • • • • • • • • • • • • • • •

V. Results . . . • • • • • • • • • • • • • • • • • • .

Figures

Figure 1 Amp Photo. . • • • . • • • . • . • • • . . . 5Figure 2 Schematic . . . . . . . . . • • • • • • • • • . 6Figure 3 Input Impedance Trade-offs • • • • • • • • • • • • •••. . 10Figure 4 Amplifier Chassis Photo . . • •• • • •. • • . • . • . . • . 12• • • .Figure 5 FET Holder Photo. . . . . . • . . . . . 13. . . • • • .Figure 6 Amplifier Performance at 300K and 15K . • • • • • • • • • • • . 16.Figure 7 Test Setup . • • • • • • • • • • • • • • • • • • • • . 18

Tables

Table 1 Noise Parameters of Mitsubishi MGF-1412 . • • • • • . 10Table II Inductor Description • . • . • • • • • • • . 14Table III Performance of Five Amplifiers • • • • • . 20

References . • • • • • • • • • • • • • • • • • • • • • • • • • • • • •

•

. . 21

Appendices

.Appendix I DC Bias Regulator Schematic . • • • • • • • • • . 23Appendix II Drawings

A. Chassis, C2613M12 . . . . . . ••••••••• . • . . .24B. Input Transformer, A2613E11 . • • • • • • • •. • . . . . 25C. PET Mount, A2613M13 . . . . . . . • • • • • • • • • • . . 25

.D. Source Bypass Assembly, A2613M14 . • • • • • • • . . 26E. Cover, A2613M15 . . • • • • • • • • . 26

Appendix III Parts List . • • • • • • • • • • • • . 27

ULTRA LOW-NOISE, 1.2 - 1.7 GHz

COOLED GASFET AMPLIFIERS

S. Weinreb, D. Fenstermacher, and R. Harris

I. Introduction

In the microwave frequency range between 1 and 3 GHz, the antenna noise

temperature due to cosmic and atmospheric sources is quite law, 5K, and it

is a challenge to receiver engineers to design low-noise amplifiers and low

ground-radiation pickup antennas to take advantage of this law source temperature.

The noise figure, in dB, of a receiver is equal to the signal-to-noise degradation

caused by the receiver when the source temperature is 290K. When the source

temperature including antenna noise is 10K, a reduction of receiver noise figure

from 1.0 dB (or a noise temperature of 75K) to 0.1 dB (6.8K) causes a signal-

to-noise improvement of (75 + 10)/(6.8 + 10) = 5.1 or 7.0 dB.

The amplifier described in this article has a noise figure of approximately

0.1 dB at 1.3 GHz. This is achieved with wide bandwidth, impedance match, excellent

stability and relatively small cost and complexity compared with masers which

have been required in the past for this noise performance. Cryogenic cooling

to a temperature of q, 15K is required but this can now be obtained with closed

cycle helium refrigerators [1] at a cost of under $5,000 and a weight less than

42 kg. Some specific applications for the amplifier are: 1) as a radio

astronomy front-end for observations of the 1.42 GHz hydrogen line and OH lines

at 1.61, 1.66 and 1.72 GHz; 2) as an I.F. amplifier for millimeter wave or

infrared receivers utilizing cooled mixers; 3) as a front-end for detection of

extraterrestrial civilizations communicating in the "optimum" frequency range

of 1.42 to 1.67 GHz [2].

-4-

In a previous article [3] a cryogenically-cooled L-band amplifier utilizing

source inductance feedback to achieve input match was described. This paper

reports on the further development of this amplifier utilizing computer-aided

design techniques to incorporate the following improvements:

1) The input circuit bandwidth has been increased by the addition of

a shunt quarter-wave line. A noise temperature variation of less

than 2K over a 500 MHz bandwidth is achieved.

2) The load impedance for the first stage has been optimized to

give > 15 dB input return loss over the same 500 MHz bandwidth

optimized for noise.

3) Series R-C bypass networks for the first-stage source and drain

and second-stage drain have been added to reduce the tendency to

oscillate at frequencies above 2 GHz. The amplifier is stable

for a sliding short of any phase placed at input or output.

4) A third stage has been added and the gain equalized to be flat

within + 1.0 dB over a 500 MHz bandwidth.

5) A chip 10 dB attenuator has been incorporated into the output

circuit to insure stability independent of out-of-band

termination impedance.

A photograph and schematic of the amplifier are shown in Figures 1

and 2. A small size was desired so that as many as 8 front-ends, for different

frequencies and polarizations, could be cooled with one cryogenic refrigerator.

II. Design

A first step in the amplifier design concerned the question of how to

handle the mismatch which results when a FET device is driven by its

optimum-noise generator impedance, Zopt . For a FET in the lower microwave

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range, this difference is quite large; typical values are Z opt = 42 + j175 and

Zin = 10 - j145, giving an input voltage reflection coefficient magnitude

of 0.73. It is, of course, possible to operate the amplifier with a large

input mismatch, but small variations of the antenna feed impedance will then

cause large ripples in the gain vs frequency response. Possible remedies to

this problem are: 1) an isolator, 2) a balanced amplifier, or 3) use of

feedback. The latter choice was taken because it results in the most compact,

fewest component amplifier and because of previous experience with this

technique [3,4]. It should be mentioned that a cooled isolator in this frequency

range has recently been developed [5].

A second major decision was whether to use lumped or transmission-line

matching elements. At 1.5 GHz this is a close decision as it is difficult to

determine the parasitic reactances of lumped elements with sufficient accuracy,

yet transmission lines are somewhat large. A compromise was made; the input

network was constructed on high-dielectric constant (10.5) transmission-line

circuit board [6] while the remainder of the amplifier was constructed with

lumped elements. The input circuit board could be easily changed to vary the

source resistance in a known manner.

A somewhat unconventional construction of the amplifier was based upon the

following considerations:

1) The lowest-noise GASFET's for use at 1.5 GHz have considerable gain

and a tendency to oscillate at 10 to 20 GHz, 'especially when source

inductance feedback is utilized. The 1.5 GHz inductors have widely

varying reactance in the 10 to 20 GHz frequency range and series R-C

bypass networks are necessary to stabilize the amplifier. For these

bypass networks to be effective, their total length must be less

-8-

than X/4 at 20 GHz ((\, 0.4 cm); they must be located extremely close

to the PET and ideally would be built into the FET package.

2) The first-stage source inductance and X/4 shunt stub length are

critical and should be easily adjustable.

The thermal resistance from the FET source leads to the amplifier

case must be low at cryogenic temperatures to avoid self-heating.

For this reason the FET source leads are soldered to a copper FET

holder with pure indium solder. The thermal resistance within the

FET package is discussed in [7].

4) A "springy" mechanical design is needed to prevent fractures due

to thermal stresses caused by the wide temperature range and

materials with different thermal expansion coefficients. For

this reason a dielectric-loaded Teflon substrate material [6]

was used even though the temperature coefficient of its dielectric

constant is much greater than that of alumina. (A 12% increase

in dielectric constant was measured for cooling from 300K to 15K).

The Mitsubishi MGF-1412 transistors used in the design were selected on

the basis of previous evaluations at 5 GHz [7] and also upon the results

reported in [3]. Noise parameters of a MGF-1412 at approximately 1.6 GHz were

measured at 300K and 15K by performing noise measurements with 3 different input

circuit boards; these had no shunt X/4 stub and had Z o values of 41, 51 and

69 ohms for the series X/4 line. The results for a drain bias of 5 volts and

10.8 mA are shown in Table I where they are compared with the theoretical values

of Pucel, et al. [8]. The agreement with theory is poor, in contrast to results

reported at 5 GHz in [7], due to low frequency noise mechanisms not accounted

for in the theory.

A MGF-1402 is used in the final stage because of its lower cost. The

amplifier output is isolated from the load by an internal 10 dB chip

attenuator [9]. Unlike an isolator, the attenuator terminates the amplifier

over the entire microwave frequency range and thus insures that the amplifier

will not oscillate for some particular out-of-band termination impedance.

Optimization of the amplifier was performed using the FARANT program

developed at NRAO [10]. The optimization trade-offs are illustrated by the

impedance plot of Figure 3 and consideration of the noise temperature dependence

upon generator impedance, Rs + jX , for any linear two-port,

gnTn = Tmin + 290 x --= [(Rs Rop t )

2

+ (Xs - X0pt)2

IRs

where Ropt + jXopt is the optimum-noise generator impedance and g n is the

amplifier noise conductance as given in Table I. The first-stage source

inductance, L10, and load reactances, C5, L5 and L2, have been adjusted to make

the FET input resistance, Rin , approximately equal to Rot. The series and

shunt X/4 line lengths and characteristic impedances and the input inductor, Ll,

are then adjusted to make Rs as close as possible to Rin and Ropt and to bring

the source reactance, X s , to a value between Xin and IfIf the shunt stub

is not present, Xs is a linear increasing function of frequency and Rs

has little frequency variation. This results in narrower bandwidth in both

noise temperature and match due to the difference between Xs and Xop t or Xin.

A more complex input circuit could give still wider bandwidth but has not been

attempted.

At the time the input impedance optimization was performed, R opt was

thought to be 75 ohms; later measurements, described in Table I, showed

Ropt = 42 ohms. However, a higher value of generator resistance gives less

pto

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-10-

TABLE I - NOISE PARAMETERS OF MITSUBISHI MGF-1412 AT

1.6 GHz, TEMPERATURES OF 300K AND 15K, AND

DRAIN BIAS OF 5 VOLTS, 10 mA.

AMBIENTTEMP

°KTmin

lignohms

Ropt

Xopt COMMENT,

300 63 + 3__ 250 + 50__ 42 + 4__ - Measured

300 20.3 1785 60.7 221 Theory [7,8]

15 8 + 2__ 1200 + 500__ 29 + 2__ - Measured

15 4.2 5882 39.3 196 Theory [7,8]

u"' X i n*

Rin= D

El opt

R s

2.01.0 1.5

Frequency (GHz )

Fig. 3. Source impedance optimization example. The minimumnoise impedance is Ropt + jXop ,t the FET input impedanceis Rin + jXin , and the generator impedance is R s + jXs.The negative slope in Xs is due to the shunt X/4 trans-mission line.

noise temperature variation with frequency and a center-frequency value

of 60.5 ohms is used in the amplifier.

III. Construction

The amplifier chassis, shown in Figure 4, is milled from a

1.27 cm x 4.07 cm x 9.15 cm block of copper which is then gold plated for

corrosion protection and to reduce absorption of thermal radiation. FET

holders, shown in Figure 5, are also machined from copper. Inductors are

fabricated as described in Table II using either gold-plated phosphor-bronze

wire or copper wire which is not as mechanically stable but is easier to

deform for tuning purposes.

The following procedures are used for soldering of components; a small

hot plate is the heat source for steps 1) thru 3):

1) The chassis is heated to 200°C and chip capacitors used as

stand-offs are soldered in 0.5 mm deep holes using solder of

62% tin, 36% lead, and 2% silver [11].

2) The chip attenuator is soldered into the chassis using a law

temperature solder [12] and flux [13] at 110°C. This same low

temperature solder can be used if a chip capacitor must be replaced

after assembly is complete.

3) The bellows contact [14] is soldered to the first-stage FET holder

using 60% tin, 40% lead solder at 200°C. The FET source leads are

then soldered into the holder using pure indium solder [15] and

flux [13] at 175°C. Drain leads are cut to 3 mm length and gate

leads are cut to 0.75 mm for stages 1 and 3 and 2 mm for stage 2.

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-13-

Fig. 5. Close-up side view of FET holder and groundingshim. The bellows contacting a 15 ohm chipresistor in series with a 0.3 pF chip capacitorto ground is used only on the first stage and isneeded to prevent oscillation at % 10 Gllz. Thesize of the holder is 2.03 cm x .41 cm x. 46 cmhigh with a .127 cm gap for the shim.

-14-

TABLE II - INDUCTOR DESCRIPTION

INDUCTOR

INNERDIAMETER

mmLENGTH

mm TURNS

INDUCTANCE, nH

COIL.

TOTAL

Ll 2.1 2.0 3 8.2 9

L2* 1.8 2.5 2 2.6 4.5

L3 1.8 0.8 1 1.4 3.5

L4 2.1 3.8 5 20.5 23

L5 - 5.8 wire 0 3.2

L6* 2.1 3.8 5 20.5 23

L7 - 4.6 wire 0 3.2

L8 2.1 3.8 2 3.2 5

L9 2.1 3.8 3 7.3 9

All wound with 0.25 mm diameter wire.

*Wind in reverse direction from other coils.

-15-

4) Starting at the output, coils and FET holders are installed using

a soldering iron and the 2% silver solder.

A rectangular bar, 1 mm x 7 mm x 27 mm, of iron-epoxy absorber material

[16] is glued into the chassis as shown in Figure 4. This material has been

tested to retain its loss at cryogenic temperatures. Berylium-copper finger

stock material [17] is soldered to the top cover with 60% tin, 40% lead solder.

Both of these items, as well as ferrite beads [18] on some of the leads, are

for the purpose of suppressing high-frequency oscillations, particularly when

the amplifier is cooled.

IV. Tuning

Tuning of the amplifier is necessary due to variability in the construction

and installation of the inductors and to meet slightly different specifications

for each application. Drain-bias voltage and current for stages 1, 2 and 3 are

initially set at 5.5 V, 15 mA, 5.5 V, 12 mA, and 4V, 10 mA, respectively.

Inductor Ll and transformer T2 lengths are trimmed to minimize the noise at a

desired frequency. The inductance of a coil may be raised or lowered by

moving the turns closer or further apart; larger changes require more or less

wire but this is usually not necessary. Inductors L2 and L10 are adjusted to

achieve input match; it may be necessary to also change Ll and T2 for this

requirement. Inductors L5, L6, L8 and L9 are adjusted to achieve the desired

gain response.

The amplifier input match vs frequency changes appreciably as it is cooled

as is shown in Figure 6. This is due to the dielectric constant change in the

input circuit board and to changes in gate-to-source capacitance caused by gate

25

1 00

50e RL

300K

IRL

Gain

14K

0 a3

1 0

--20

— 30

N.• IMO

20

1 I

Noise /

mum

Noise

01.0 1.5

Frequency (GHz

ONO 00. N.

202.0

Fig. 6 . Input return loss (IRL), gain, and noisetemperature of amplifier #74 at 300K (top)and 14K (bottom). Note scale change fornoise temperature.

-17-

bias voltage changes necessary to keep drain current in an optimum noise range.

To some extent the input match change can be compensated by pre-tuning at 300K

for the triangle shape shown in Figure 6. This is often not satisfactory and

iterations of tuning and cooling may be necessary. Tuning of the amplifiers

attached to a copper block in liquid nitrogen has been a useful procedure;

little change in input match occurs between 77K and 20K.

V. Results

Amplifiers are tested for input return loss and gain utilizing a scalar

network analyzer [19]. For the return-loss measurement, test signal power level

at the amplifier input is -25 dBm and is somewhat critical; a higher level

causes an error due to second-stage overload and a lower level gives insufficient

reflected power for the reflectometer bridge sensitivity. For gain measurement,

the input signal level is -45 dBm.

Noise temperature and also gain are measured with the test setup shown in

Figure 7. The amplifier is mounted in a vacuum dewar and is thermally connected

to a cryogenic refrigerator. The amplifier input is connected to the dewar

exterior thru a very low loss (.08 dB, later reduced to .04 dB) coaxial line

with APC 3.5 connectors and length 8.5 cm. This line has crystalline quartz

inner conductor supports to form a vacuum seal and to insure that the amplifier

end of the inner conductor is at the refrigerator temperature; the line will

be described in detail in a future report.

Noise from a semiconductor-diode noise source [20] is coupled to the

amplifier input thru the side arm of a 20 dB directional coupler. The main

arm of the coupler is connected to a cold termination in the dewar to increase

accuracy by preventing addition of a large room temperature noise to the

Tes

tR

ecei

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App

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IA 41

1111

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116

11111111

1111111 •

1111

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111,

Am

pU

nder

Tes

t

15K

300K

1

A

HP

346B

Noi

seS

ourc

e

20 d

BC

oupl

er

Cry

ogen

ic

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Vac

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Com

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13

00

K 1

5K

LO

Contr

ol

Fig. 7. Test setup for amplifier noise and gain measurements. Very low loss coaxial-line

transitions were developed for connection, A to B, to the amplifier.

-19-

small amplifier noise. By replacing the coupler output, point A in Figure 7,

with hot and cold noise temperature standards, the noise temperature at point A

with diode off, 28.8K, and diode on, 94.1K to 123.7K dependent upon frequency,

was calibrated. The noise diode was then turned on and off as receiver local-

oscillator was scanned to give a swept-frequency measurement of noise temperature.

A prior scan with the amplifier bypassed allows computation of the amplifier

noise temperature, corrected for test receiver noise, and also the amplifier

gain. This procedure is performed by an Apple II computer.

At the time of this writing, 16 amplifiers have been constructed. All

amplifiers are stable for a sliding short of any phase connected to input or

output. Oscillation of an amplifier can be detected either by observation of

a bias value change or by observing the output of a broadband detector connected

to the amplifier input or output port.

Noise temperature, gain, and input return loss for one amplifier are shown

in Figure 6; this amplifier had the lowest noise temperature, 7.2K, but is

typical in gain and input match. The noise temperature is referred to the cold

amplifier input connector and is believed to be accurate within + 0.5K; a value

of 8.3K was measured at point A, outside of the dewar. Characteristics of four

additional amplifiers are given in Table III; the noise temperatures of these

amplifiers are only known to an accuracy of + 2K and are also referred to the

amplifier input connector.

-20-

TABLE III - PERFORMANCE OF FIVE AMPLIFIERS

UNIT NUMBER

AMBIENT TEMP °K

74

14

75

17

83

14

84

14.1

86

15.4

STAGE I BIAS, VD 5V 5V 5.5V 5.5V 5.5V

ID 10.7 mA 10 mA 12.4 mA 10.1 mA 6.7 mA

VG -.713 -.592 -.598 -.750 -.684

NOISE TEMP* MIN 7.2K 8.6K 9.0K 8.4K 11.6K

fMIN 1260 1320 1320 1360 1360

FREQS FOR

INPUT RETURN fi, 1160 1220 1150 1260 1300

LOSS > 15dB H 1640 1720 1620 1625 1800

GAIN MAX 25.5 dB 33.5 dB 30.4 dB 30.8 dB 31.2 dB

-3 dB fl,

f-3 dBH

1150

1850

1190

1820

1050

1850

1150

1750

1100

1950. __

Noise temperature referred to amplifier input connector at 15K. Values at roomtemperature connector are 1.1K to 3.0K higher.

-21-

REFERENCES

[1] Model 2 Cryogenic Refrigerator, Cryosystems, Inc. Westerville, OH.

[2] B. M. Oliver and J. Billingham, "Project Cyclops," Design Study

Report CR114445, NASA Ames Research Center, Moffett Field, CA.

[3] D. R. Williams, W. Lum, and S. Weinreb, "L-Band Cryogenically-Cooled

GaAs FET Amplifier," Microwave Journal, Vol. 23, No. 10,

October 1980, pp. 73-76.

[4] L. Nevin and R. Wong, "L-Band GaAs FET Amplifier," Microwave Journal,

Vol. 22, No. 4, April 1979, p. 82.

[5] Model LTE 1102, Passive Microwave Technology, Canoga Park, CA 91304.

[6] RT/Duroid 6010, .050" Dielectric, 2 oz., 2 Side Copper, Rogers Corp.,

Chandler, AZ.

[7] S. Weinreb, "Low-Noise Cooled GASFET Amplifiers," IEEE Trans. on Microwave

Theory and Tech., Vol. MTT-28, No. 10, October 1980, pp. 1041-1054.

[8] R. Pucel, H. Haus, and H. Statz, "Signal and Noise Properties of Gallium

Arsenide Microwave Field-Effect Transistors," Adv. in Electronics

and Electron Physics, Vol. 38, L. Morton, Ed., New York: Academic,

1975.

[9] Type PCAW-10, KDI Pyrofilm, Whippany, NJ.

[10) D. Fenstermacher, Electronics Division Internal Report No. 217, National

Radio Astronomy Observatory, Charlottesville, VA.

[11] Type SN62 Solder, 179°C, Multicore Solders, Westbury, NY.

[12] Type 20E2 Solder, 100°C, Alpha Metals, Jersey City, NJ.

[13] Type 30 Supersafe Flux (water soluble), Superior Flux and Mfg. Co., Cleveland, OH.

[14] Type 2156 Bellows, Servometer Corp., Cedar Grove, NJ.

-22-

[15] Indalloy No. 4 Solder, 157°C, Indium Corp. of America, Utica, NY.

[16] Eccosorb Type MF-124, Emerson and Cummings, Canton, MA.

[17] Type 97-500G Finger Contact Strip, Instrument Specialties Co.,

Delaware Water Gap, PA.

[18] Type T10-6 Ferrite Core, Micrometals Inc., Anaheim, CA.

[19] Type 560 Scalar Network Analyzer, Wiltron Inc., Palo Alto, CA.

[20) Type 346B Noise Source, Hewlett-Packard Co., Palo Alto, CA.

750K

1 II +15

100K

2K

10

499K

7 .

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INPUT TRANSFORMER

Appendix II.B.

.800

ROGERS 6010 DUROID

2 OZ. COPPER BOTH SIDES,GOLD PLATE

TOLERANCE, ±.001

REV: 9/4/81

K=10.5 ±.5.050" THICK

SCALE= 5:r REV: 7/10/81

ADJUSTABLE SHORT MAT'L.- 0.050 BRASS

GOLD PLATE

NATIONAL RADIO ASTRONOMYOBSERVATORY

TITLE: INPUT TRANSFORMER 81ADJUSTABLE SHORTL -BAND AMP.

:osGN.sv:S.WEINREB IDATE:10/ 26/80APPD.BY:DR.BY:

_DWG. NO A 2613 Ell

.445.08 .275 t . 350

.070.160

.288

A= DRILL 8 C/S FOR 2-56 FT. HD., M. S. (.086 D.) 2 Plcs. 1.04

.060

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MAT'L: OHF C OR ETP COPPER; GOLD PLATE

TOL: .000 = .002.0000 = ±.0005

ITEM - 2 SHORTING BAR

.05O THICK BRASSOR COPPER; GOLD PLATE

.078-4- . 71

f...068-t-.071

I..NOTCH-ONLY FIRST STAGE,LEAVE OFF 2nd & 3rd STAGE.

SCALE =10:1

)-1

.100

1.065

NATIONAL RADIO ASTRONOMYOBSERVATORY

,TITLE:FET MOUNTL-BAND AMP.

. .OSGN.BY,S.WEINRE DATE: 3/16/81APPD.BY: DR.BY:

-DWG. NO A 2613 M13Appendix II.C.

E 3 .078-7r-

. 06 1

15

SERVOMETER 2146 BELLOWSR-15nRESISTOR, MINI-SYSTEMS

WA-4 .105C-0.3pF CAP., 0.050 CUBE

.060

140—.109crl

.210

AMPLI FIERCASE

. .NATIONAL RADIO ASTRONOMY

OBSERVATORY

TITLE: 4i..FIRST STAGE SOURCE BYPASSASSEMBLY DRAWING

, L—BAND AMPosGN.Ercs,WEINREBIDATE: 3.16180APPD.8Y: 'DRAIN':DWG. NO A 2613 M14, .

Appendix II.D

1.174

+.0002.53—.03°2

/

NATIONAL RADIO ASTRIatiOMYOBSERVATORY ' r

TITLE: COVERL — BAND FET AMPLIFIER

:osGN.sy :S.WEINRE DATE: 9/81APPO.BY: jDR.8Y:DWG. NO A 2613 M 15, .

.160

CLEAR 4/40, C/S B.S.FOR FT. HO. M.S. (5plcs)

.400.115

.250 ITEM-1,0.065" Thick, ETP OR OFHC COPPER, GOLD PLATE.ITEM-2, = Instrument Specialties —(97-500 G ) FINGER STOCK

Appendix II.E

PARTS LIST

L-Band FET Amplifier

DATE

9/3/81

REVISION

ITEM

QUANTITY

REF.

DE

SIG

.D

ESC

RIP

TIO

NM

FG.

PART

NU

MBE

R

11

Ch

assi

sNR

AOA2613M12

1Cover

NRAO

A2613M15

1:Inp

ut S

hort

NRAO

A2613E11

3FET Mount and Ground Shim

,

NRAO

.

A2613M13

Finger Stock Material

Instrument Specialties

97-500G

_Microwave Absorber

Emerson-Cumming

MF-124

4T

oro

idM

icro

-Met

als

T10

-6

81

Bellows

Servometer

2146

91

Microwave Circuit Board, E=10.5,

.050"

die

lectr

ic,

2 oz. 2 side copper

Rogers

6010-.050

105

4-40 x 1/4" Flat Head Screw, S.S.

All-Metal Screw Products

116

2-56 x 1/4" Flat Head Screw, S.S.

All-Metal Screw Products

1210

2-56 x 1/8" Binding Head Screw, S.S.

All-Metal Screw Products

131

2-56 x 1/4" Binding Head Screw, S.S.

All-Metal

Scr

ew Products

142

SMA Female Flange Connector

Omni-Spectra

204-CC

151

7-P

in P

ow

er Connector

_M

icro

-Tec

hER-7S-6

PARTS LIST

L-Band PET Amplifier

DATE

9/3/81

REVISION

ITEM

QUANTITY

REF.

DESIG.

DESCRIPTION

MFG.

PART NUMBER

16Solder, B20E2,

.032 diameter

Alpha Metals

B20E2-.032

17Solder, 60/40, Rosin Flux

Ersin

Sn60

18Solder, 100% Indium

Indium Corp.

Indalloy 4

19Solder, 2% Silver

Ersin

Sn62

20Flux, Supersafe

Superior Flux & Mfg.

#30

21

Flux, Rosin Liquid

Rester

#1544

22Hookup Wire, #30 Enamel

Belden

8055

23

Hookup Wire, Tinned #24

Belden

8022

24Wire, Phosphor-Bronze,

.008" dia.,

gold-plated

California Fine Wire

25Wire, #32 Copper

Any

261

Attenuator, Chip, 10 dB

KDI Pyrofilm Corp.

PCAW-10

272

Ql,

Q2

PET

Mit

sub

ish

iM

GF-

1412

281

Q3

PET

Mit

sub

ish

iM

GF-

1402

2912

C13 thru

C24

Chip Capacitor, 680 pf, 100 mil

ATC

ATC-100-B-681-K-P

305

C7,

C8,

C9Cll, C12

Chip Capacitor, 22 pf, 100 mil

ATC

ATC-100-B-220-M-P

PARTS LIST

L-Band FET Amplifier

DATE

9/3/81

REVISION

ITEM

QUANTITY

REF.

DESIG.

DESCRIPTION

i

MFG.

PART NUMBER

313

C2, C3, C4

Chip Capacitor, 16 pf, 50 mil

ATC

ATC-100-A-160-K-P

32_

2Cl, C10

Chip Capacitor, 22 pf, 50 mil

ATC

ATC-100-A-220-K-E.

332

C5

, C

6Chip Capacitor, 1

p

f, 5

0 m

il

ATC

ATC-100-A-1RO-B-P

341

C25

Chip Capacitor,

.3 pf, 50 mil

ATC

ATC-100-A-OR3-B-P

352

R1, R2

Chip Resistor, 50 ohm

Mini-Systems

WA4PG-500J-S

36

1R9

Chip Resistor, 15 ohm

Mini-Systems

,

WA4PG-150J-S

37,

3R

6, R7, R8

Resistor, 1000 ohm

Corning

RLRO5C-1001-FR

38,

2R3, R4

Resistor, 49.9 ohm

Corning

RLRO5C-49R9-FR

392

R5, R10

.

Resistor, 100 ohm

Corning

RLRO5C-1000-FR

403

CR1, CR2, CR31

Diode, Zener

,Motorola

1N4099

413

CR4, CR5, CR6

Diode

Zener Reference

_

Motorola

1N821

-30-

VENDOR LIST

Manufacturer/Vendor

All Metal Screw Products9051 Baltimore National PikeEllicott City, MD 21043(301) 461-3434

Alpha Metals/Q. C. Electronics16 Highwood AvenueEnglewood, NJ 07631(201) 569-0975

American Tech Ceramics (ATC)1 Norden LaneHuntington Station, NY 11746(516) 271-9600

Belden/Virginia Radio Supply715 Henry AvenueCharlottesville, VA 22901(304) 296-4184

California Fine WireP. 0. Box 446Grover City, CA 93433(805) 489-5144

Corning/Milgray-Washington11820 Parklawn DriveRockville, MD 20852800-638-6656

Emerson-Cuming59 Walpole StreetCanton, MA 02021(617) 828-3300

Ersin/Techni-Tool, Inc.5 Apollo RoadPlymouth Meeting, PA 19462(215) 825-4990

Indium Corp. of America1676-1680 Lincoln AvenueUtica, NY 13502800-448-9240

Instrument SpecialtiesP. O. Box ADelaware Water Gap, PA 18327(717) 424-8510

Manufacturer/Vendor

KDI Pyrofilm Corp.60 S. Jefferson RoadWhippany, NJ 07981(201) 887-8100

Kester/Virginia Radio Supply

Micro Metals1190 N. Hawk CircleAnaheim, CA 92807(714) 630-7420

Micro Tech, Inc.1420 Conchester HighwayBoothwyn, PA 19061(215) 459-3566

Mini-Systems, Inc.20 David RoadNorth Attleboro, MA 02761(617) 695-0203

Mitsubishi Electronics/America, Inc.1230 Oakmead Parkway, Suite 206Sunnyvale, CA 94086(408) 730-5900

Motorola/Hamilton Avnet6822 Oak Hall LaneColumbia, MD 21045800-638-1772

Omni-Spectra21 Continental BoulevardMerrimack, NH 03054(603) 424-4111

Rogers Corp.P. O. Box 700Chambler, AZ 85224(602) 963-4584

Servometer Corp.501 Little Falls RoadCedar Grove, NJ 07009(201) 785-4630

Superior Flux & Mfg. Co.95 Alpha Park .Cleveland, OH 44143(216) 461-3315

Appendix III