US Army Signal Corps
Test Sets & Test Instruments

Test sets used for maintenance of ground communications equipment.
Nearly all these test sets are components of Test Equipment (IE) or Test Packages,
however they may also be used as separate units.

click on the photo for full size view!

I-23 Voltammeter

Part of IE-29

Small meter for battery testing; scale ranges, 0-35 amp, and 0-11 volts; with 10 in, cord.

I-48-B Test set

Part of TE-56-A

For measuring resistance 0-1000 megaohms. 500 volt. Single range. “Megger”.

I-49 Test Set

Part of IE-10

Portable decade type Wheatstone Bridge for use of wire chief, line repairmen and maintenance man. For maintaining open wire and field wire circuits, and short haul cable circuits in small offices only, and for location of grounds, crosses, and shorts. Cannot readily be used for open location and capacitance measurements. Requires use of 3 batteries BA-30.

I-50 Voltammeter

Part of IE-29

DC, triple range, scale ranges 0-3, 0-15, 0-150 volts and 0-3, 0-15 and 0-30 amperes.

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I-51 Test Set

Part of IE-29

Cable repairman's portable tone test set, for locating shorts, grounds, crosses, split pairs and wet spots in cables. Consists of a tone supply from a spark gap induction coil. Includes an exploring coil (W.E.Co. 19C Test Set) and receiver, cord and plug all of which comprise W.E.Co. l0l9C Test Set. Has high output and therefore will introduce noise in parallel circuits. Requires 4 Batteries BA-23.

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I-53 Test Set

Part of IE-


I-56 Test Set

Part of IE-26

A universal radio test set. Consists of a group of instruments for servicing radio equipment; output meter, tube tester, meters for measuring current, voltage and resistance In various ranges, in carrying case.

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I-61-A Test set

Part of IE-10 and IE-29

Transmission measuring set; portable, dry battery operation. To measure losses or gains in circuits or apparatus, Includes 1000-cycle oscillator, receiving amplifier, rectifier and meter. Oscillator has outputs -40, -20, and 0 dbm into a 600 ohm load. Will measure power from a 600-ohm source between -50 and +15 dbm over a frequency range from 100 to 10,000 cycles. No spare tubes included, Requires 5 Batteries BA-30 and 3 Batteries BA-56.

I-61-B and C Test Set

Part of IE-10 and IE-29

Same as I-61-A except: oscillator transmits 500, 1000 and 2500 cycles, includes local battery telephone, spare tubes, no batteries, Requires following batteries: two BA-30, three BA-45 and two BA-36.

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Part of IE-


I-72 Signal generator

Part of IE-9 and IE-26

Self-containing; for operating on a 105-130 volts, 60 cycle (3F3852.1) or 25 cycle (3F3852.2), single phase power Frequency range 100-32.000 kc, with provisions for 400-cycle modulation. Intended for vehicular use.

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I-76 Test set

Part of IE-26

Test Oscillator BC-276 with tubes and batteries, test indicator BE-67 with batteries and cords and headset HS-23. Replaces I-66. For aligning marker beacon receivers.

I-83-A Test set

Part of IE-9 (alternate)

Dynamotor test set; for measuring input current and voltage, output current and voltage and input and output ripple voltage of various 12 and 28 volt dynamotors and dynamotor units. Includes socket and cords.

I-87 Test meter

Used with but not part of SCR-293 and SCR-294

Tuning meter (0-100 ma) and micro-ammeter (center 0) mounted in a case. For adjusting transmitter and receiver to proper operation frequency. Includes cord and plug for connecting to receiver or transmitter under test.

I-95 Field Strength meter

Part of IE-12 and IE-19

For determining relative field strength readings and a rough over-all check of transmitter operation, Tube VT-172 ( JAN-1S5) supplied separately. Requires 2 Batteries BA-5 and 1 BA-23

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I-96 Signal Generator

Part of IE-12

Provides signals for testing radio receivers and measuring equipment for metering the transmitter output , Includes milliammeter. For tuning and aligning BC-684 receiver and BC-625 transmitter.

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I-97-A Bias Meter

Part of EE-97 and EE-98

Portable field meter of the zero center type, used with Line Unit BE-77 for normal adjustment of teletypewriter circuits. Not required with BE-77-A or -B.

I-107 Voltohmmeter

Part of ME-13

Vacuum tube, dc, battery operated; ranges 0,1 to 10 megohms in 6 steps, 3 to 1000 volts full scale in 6 steps; input resistance 10 megohms on all voltage scales. Requires 5 Batteries BA-30 and 1 Battery BA-40.

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I-126 Signal generator

Part of IE-

Test instrument designed to furnish a signal of desired radio frequency, used for alignment of radio receivers.
Band A: 15-25 megacycles.
Band B: 195-225 megacycles.

I-129 Frequency meter set

Part of IE-9

Consists of four absorption type wave meters contained in a steel carrying case. Frequency range l.5 to 40 mc.

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I-130 Signal Generator

Part of IE-19

Portable frequency band 100-156 megacycles. Uses separate battery supply. Requires 6 Batteries BA-2 and 4 Batteries BA-23. For tuning Radio Receiver BC-624 and Radio Transmitter BC-625.

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I-135 Test unit

Part of IE-17

Case containing multi-range meter, RE and AF oscillators, receiver, microphone, crystal tester, switches, terminals, test harness, etc. Requires one Battery BA-23 and two Batteries BA-26.
SCR 536.

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I-139 Test set

Part of IE-19

Meter contained in metal case; 0-1 ma, dc; designed for measuring current in 2 positions in Signal Generator 1-130-A, in 5 positions in Radio transmitter BC-625 and 1 position in Radio Receiver BC-624; includes cord and plug.


Part of IE-

A composite measuring instrument designed for measuring the electrical characteristics of telephone equipment.

I-151 Oscillator

Part of IE-

Audio oscillator with a frequency range of 20 cycles to 20.000 cycles in 3 bands. Power input 110-120VAC 60Hz.

I-153 Analyzer

Part of IE-9 (Alternate for I-167)

Multimeter 0-6,000 volts; dc 20.000, ac and dc 1,000 ohms per volt; 7 ranges 0-60 microamp.  to 12 amp.; resistance 0-60 meg; six db ranges, +12 to +70 db, and 7 output ranges. Requires 1 Battery BA-2 and 1 Battery BA-30.

I-157 Test Set

Part of IE-

Tube and set tester, Precision Model 920P

I-166 Voltohmmeter

Part of IE-29, IE 53, test set I-56

Voltage ranges; ac, 0-500V; dc, 0-5, 0-15, 0-50, 0-150, 0-500, 0-1500. Resistance ranges; dc, 0-1000, 0-10,000, 0-100,000 ohms and 0-1 megohm. Measures audio frequency output voltage at 4000 ohms impedance, ranges 0-1.5, 0-5, 0-l5, 0-50, 0-150 volts; and at 300 ohms impedance, ranges 0-5, 0-15, 0-30 volts, Requires 1 Battery BA-31.

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I-167 Analyzer

Part of IE-9

Meter. Voltage ranges 2,5-l000V. in five steps ac and dc; current, 100 microamperes to 10 amperes in 7 steps, dc; resistance, 3,000 ohms to 30 megohms in four steps; decibels -14 to +54. Requires 1 Battery BA-30 and 2 Batteries BA-34.

I-171 (Hickok Model 560) Tube Tester

Portable tube tester for small size amplifier and rectifier tubes, etc, Power required, 60 watts, 105-125volts, 50-60 cycles , ac, Replaced by I-177.

I-176 Test unit

Part of Test set I-56

Combined ac and dc voltammeter and ohmmeter, complete with test leads; can be used to check voltage between any two elements of a tube and current through tube when in operating circuit; ranges as follows:
DC: 0-5/25/100/250/1000/5000V - 20.000 Ohms per V.
AC and DC: 0-5/25/100/250/1000V - 1.000 Ohms per V.
DC: 0-1/5 Amp.
AC: 0-0,5/1/5/10 Amp.
0-1000/100.000/10.000.000 Ohms
DC: 0-1/10/100/500 mA.
DC: 0-50 microAmperes.

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I-177 Tube Tester

Part of IE-9, IE-29 or test set I-56

Portable tube tester of the dynamic or mutual transconductance type capable of operation on 110 or 220 volts, 50-60 cycles ac, Replaces I-171.

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Part of IE-

I-181 Test set

A portable current flow test set for use in testing and adjusting relays (and similar apparatus) in accordance with electrical requirements for performance of the relay. Provides for application of specified values of current thru the relay winding. May also be used as milliammeter in scale range 0-15, 0-75, 0-150ma.

I-193-A Test set

Polar relay test set. For testing and adjusting W.E.Co. telegraph polar relays 255A, D-163119A and D-164618. Includes special adjusting tools for these relays. Test set also provides source of 10 or 20 cycles “open-and-closed” signals for lining up the X-61822 carrier telegraph system. Cords supplied for connecting to DC power source, or to rectifier such as RA-37 or RA-87. Power required, 10 watts, 115-130 VDC.

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I-199 Test Set

Part of IE-9

Dynamotor  test set, two-meter instrument, measures input and output voltages, current and ripple. Replaces test set I-83-A.

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I-208 Signal Generator

Part of IE-9

Frequency ranges 1,9 to 4,5 megacycle and 19,0 to 45,0 megacycles. Frequency mod. Generator. Can be operated from l2-volt vehicular battery or from a 115-volt 60-cycle AC source. Used for calibration, sensitivity check and alignment purposes.

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I-209 Test Set

Part of IE-


I-210 Alignment Indicator

Part of ME-13 and ME-40

An electronic alignment unit, with electron ray tube VT-2l5. Optional replacement for Voltohmmeter 1-107 in Maintenance Equipment ME-13. Requires 1 Battery BA-39.

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I-222 Signal Generator

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I-223 Range Calibrator

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I-236 Test Unit

Part of TE-50

Neon and Mazda lamp AC and DC voltage check unit used in maintaining teletypewriter equipment, to check the continuity of circuits which may or may not contain a “voltage”.

BC-1052 Analyser

Part of SCR-399 and SCR-499

Analyzer with multiplier for readings up to 3000 volts. Used with but not part of Radio Set SCR-299. Used with and part of Radio Sets SCR-399 and SCR-499.

EE-65 Test Set

Wire chief's portable compact testing equipment for field and central office use. Includes telephone set, hand generator, buzzer, voltmeter  (3.000 ohms) and 5 circuit switching keys, Voltmeter range 0-50 VDC. For maintenance of common battery and magneto telephone equipment, station lines and trunks. Tests for grounds, crosses, shorts, opens,  line capacitance to ground or to other lines and distance to an open;  measures insulation resistance 500-115,000 ohms using conversion table of TM 11-361. Provides for talking and signalling to switchboards and  telephones. Requires 1 Battery BA-1 and 2 Batteries BA-2. Replaced by Teat Sets TS-26/TSM and TS-27/TSM.

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EE-65-A and B Test Set

Same as EE-65 except has 50,000 ohm voltmeter; measures insulation resistance of 10,000 ohms to 2 megohms; requires 2 Batteries BA-30 and 2 Batteries BA-2; and the following must be supplied separately: 1 Handset TS-9 equipped with Plug PL-58 or 1 Headset HS-30 equipped with Cord  CD-605 and Chest Set TD-l, 1 ground rod, and 1 Coil C-61 (W.E.Co. l2A) or  W.E.Co. 12S. Replaced by Test Sets TS-26/TSM and TS-27/TSM.

EE-65-C,D,E,F & G Test Set

Same as EE-65-A or B except has 6 keys; measures also loop resistance of  22 to 10,000 ohms by using conversion table of TM 11-361; and does not  require use of l2A or 12S coil. Replaced by Test Set TS-26/TSM and TS-27/TSM.

SCR-211 Frequency meter set

Part of IE-9 or IE-26

Consists of frequency meter for calibrating radio transmitters and  oscillating receivers by direct comparison.

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TS-2/TG Test set

Portable teletypewriter signal distortion test set for sending normal and distorted (up to 50%) test signals for checking the quality and for lining up teletypewriter equipments, regenerative repeaters and teletypewriter circuits. The signal send from motor-driven cams by an AC series governed motor, adjustable for speeds of 368 or 404 cpm. Test signals may be a test message, repeat space, R or Y. Equipped with jacks and resistors to provide 60 mil local circuit (DC power from external source) for checking performance of teletypewriters. Power input requirements: 150 VA at 115 VDC 50/60 cycles AC for motor power; 7W at 115VDC for local test circuit.

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TS-26/TSM Test Set

Maintenance and lineman’s multirange voltohmmeter, to maintain common  battery and magneto office equipment, and lines. Tests for grounds, crosses, shorts and opens, line capacitance to ground or to other lines, and distance to an open on a line. Voltage scale ranges 0-600VDC; resistance 0-1 megohm, or 0-10 megohms if 45V test battery is used. Requires 1 Battery BA-31.

TS-27/TSM Test Set

Maintenance and lineman’s portable field wire testing and fault locating set. Provides direct current bridge for measurement of conductor and insulation resistance, and the location of grounds, crosses and shorts, and an alternating current bridge for measurement of capacitance and location of open. A telephone set such as Telephone EE-8 may be connected for two-way talking and signalling between maintenance groups. Requires 2 Batteries BA-30 and 2 Batteries BA-59 or BA-63.

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TS-32/TRC-1 Test Oscillator

Crystal-controlled test oscillator with provision for 1000-cycle frequency modulation of output signal in frequency range of 70-100 mc with 200 kc separation. Includes provision for alternating and indicating RF outputs. Used to adjust and align Radio Receiver R-19/TRC.

TS-190 Test set

Part of IE-53

High resistance test receiver, for making trouble locating tests. Used in checking points in circuits for presence of battery or ground; and for continuity through contacts. When bridged across a contact, a click in the receiver indicates the contact is not making. Also may be used for monitoring. Has leads equipped with test pick and a socket type connector. The test pick includes a switch which short-circuits a 50.000 ohm resistance is series with the receiver. Receiver approximately 1.000 ohms.

Western Electric Co. No.5A


Small portable attenuator for introducing 600 ohm impedance balanced losses of from 0 db to 81 db in steps of 1 db. Suitable for use up to 100 kilocycles. 

Western Electric Co. No.13A

Transmission Measuring Set

Portable test unit for measuring testing power over frequency rang of 30 cycles to 15 kilocycles; input impedance approximately 600 ohms; can be used to measure received power from -45 db to +10 db. An external source of testing power of 1 milliwatt is required for gain or loss measurement. Power required for operation of set, 50 watts, 105-125 volts either DC or 25-60 cycles AC.

Western Electric Co. No.19C

Test Set

Exploring coil. See W.E.Co. No 1019C and 1119C Test Sets.

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Western Electric Co. No.19C (Spl)


Heterodyne-type vacuum tube oscillator which provides a source of  testing current for transmission measurements; is capable of supplying an output from -4 dbm to +6 dbm over a frequency range from 30 cycles to 15 kilocycles. One control dial serves to vary the frequency continuously over the full range. For greater precision as to frequency in the range below 250 cycles, an expanded sale is provided on the same dial. Employs five vacuum tubes; output impedance 600 ohms, Power required, 25 Watts, 105-125 Volts, either DC or 50-60 cycles AC.

Western Electric Co. No.32A

Transmission Measuring set

Portable test unit for measuring testing power over frequency range of 150 cycles to 150 kilocycles. Power from 600 ohm circuit can be measured either on a  terminated or a bridging basis over a range of -35 dbm to +34 dbm. Includes an attenuator, range 35 db in 5 db steps. A l35-600 ohm impedance ratio repeating coils included for measurements on 135 ohm circuits. Power input required 50 watts, 105-125V, 50-60 cycles AC.

Western Electric Co. No.51A


The 5lA Oscillator per X-66065B is a portable unit capable of supplying single frequencies from 2 kilocycles to 79 kilocycles in one-kilocycle steps. A 0 KC to –1 KC control permits the frequencies to be continuously varied from 0 to -l kilocycle from the indicated value. A minimum frequency of proximately one kilocycle may be obtained. Output ranges from +16 to -75 dbm. Output impedance 135 ohm; requires use of l35:600 ohm repeating coil when employed for supplying testing power to 600 ohm circuits. The repeating coil included in the 32A Transmission Measuring Set may be used for this purpose. Requires 60 watts; operates on 105-125 Volts, 50-60 cycles AC.

Western Electric Co. No.76A

Test Set

Part of TE-56

Cable splicer’s portable tone test set consisting of a tone supply from a battery operated vacuum tube oscillator. Used with W.E.Co. l08A Amplifier, l0l9C or  1119C Test Set and W2BK cord equipped with 47B and 186 plugs for locating shorts, grounds, crosses, split pairs and wet spots in cables. Has a lower output than the Test Set I-51. Cable splicer can signal and talk to wire chief or maintenance man having a 76A Test Set. Requires 2 Batteries BA-2 2 Batteries BA-27 

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Western Electric Co. No.108A


Part of TE-56

For use with W.E.Co. 76A Teat Set, l0l9C or lll9C Test Set and W2BK cord equipped with 478 and 186 plugs in cable testing, fault locating for identifying wires in cables. Consists of 107A Amplifier, W2BJ cord equipped 513A tool and No. 47B plug and R2CF cord equipped with 528 Receiver and No.110 plug. Requires 1 Batt. BA-27, 2 Batt. BA-2.

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Western Electric Co. No.1017E

Test Set

Line repairman' s telephone. Talking and listening. Also signalling to all switchboards and telephones. 20-cycle hand generator and buzzer. Will operate a 56A drop through 11,500 ohms. Consists of  W.E.Co. 17E Test Set with transmitter and receiver. Requires 1 Batt. BA-27.

Western Electric Co. No.1019A

Test Set

Part of test set I-51, Part of TE-56

Replacing coil (W.E.Co. No. 19C Test Set) and 1 No. 528 or No. 716B Receiver equipped with RC2D cord and No.186 plug; for use in locating various resistance conductor faults in cable. If difficulty is experienced in hearing tone pickup, W.E.Co. No.l08A Amplifier may be used with No. l0l9C Test Set, requiring the use of W2BK cord equipped with No.47B and No. 186 plug. Used with W.E.Co. No.76A Test Set.

Western Electric Co. No.1119A

Test set

Same as W.E.Co. No, l0l9C Test Set, except includes 2 No, 528 or No.716B receivers equipped with a No.1B headband and R2CC card with No.186 plug, instead of single receiver.

Western Electric Co. No. D-166852


Portable meter, Ranges; voltage AC or DC, 0-3, 0-15, 0-30, 0-150, 0-300 volts; current DC, 0-150 milliamperes, 0-3, 0-15 amp; resistance, 0-1.000, 0-10.000, 0-100.000, 0-1.000.000 ohms. Is equipped with 4½ volt battery. Includes two pairs of test leads, one pair equipped with test picks, the other with test clips. Carrying case and Carrying Strap are not included as part of the meter.

Western Electric Co. No. D-169370

Volt-Ohm-Milliameter (Multimeter)

May be supplied in place of I-166 in IE-53

Volt-ohm-milliammeter (Multimeter) similar to W.E.Co. D-166852 meter, but with test lead reversing switch, provision for connection of external 45V battery and 0-10 megohm scale. Will perform same functions as Test Set TS-2S6/TSM by connecting of external 45 V Battery BA-59. Includes pair of test pick leads (W.E.Co. KS9290) and pair of test clip leads (W.E.Co. KS9291). W.E.Co. Carrying Case KS-9370 may be used to contain meter and external battery, and Strap W.E.Co. KS-9308 for carrying meter or carrying case, but are not included as part of meter.

Western Electric Co. No. ES-800092

Patching and Power Cable Test Set

Part of IE-23

Portable teat set for testing power and patching cables terminated in 4- or24-conducter Jones type plugs, for continuity, shorts and crosses. Required cords supplied with test set and with filter Center and Information Center equipment.

Teletype Corp. No DXD-1

Test Set

Signal distortion test set for use largely in maintenance depots and repair shops. Test signals transmitted from set may be distorted from 0 to 100%. Signals measured by means of a stroboscope containing a small neon lamp. Transmitted signals are test message, R and Y, A

Teletype Corp. No DXD-4

Test Set

Same as Teat Set DXD-1 except arranged to send “blank” T, O, M, V or “letters” signals in addition to the test message, R and Y signals. Supplied with all required cords. Motor unit and gears are ordered separately.

Teletype Corp. 103628

Tuning Fork

Part of TE-50

87.6 VPS tuning fork for use in adjusting speed of teletypewriter motor to American Standard of 368 OPMI.

Teletype Corp. 104984

Tuning Fork

Part of TE-50

96.19 VPS tuning fork for use in adjusting speed f teletypewriter motor to British Standard of 404 OPM.

Serie 910 Electronamic Tube Tester
Precision Apparatus Company
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Model 804
Tube Tester - Set Tester
Radio City Products Co.Inc.
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MX 949
Extension kit for I-177
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