OSCILLATOR No. 87A and 87B
Oscillator No. 87B is a 1 kHz Transistor Oscillator. The Oscillator is housed in a metal case and is normally carried in a Satchel No. 3B.

The Oscillator is operated from a 4.5v supply "Battery Dry No. 23" and provides a 1 kHz tone source of 10mW into 300 ohms and has been designed for use with Amplifier No. 109 for Cable pair identification.

Output frequency: 1Kc/s continuous, or interrupted 2-20 p.p.s. at  15mW.

Used for cable and cable pair identification.

Part of Tester No. 132.

To be requisitioned separately as required:-
1 x Battery, Dry No. 23.
1 x Cord, Test No. 2/72AT.
1 x Plug No. 420 with Cord, Instrument 2/138AB 54".
1 x Receiver Headgear No. 16T.
1 x Satchel No. 3A.

Drawings - 91140, 91276, 91668 and 61688.

Circuit Diagram - SA9132.

Specification - D2112.


Oscillator No. 87A



Oscillator No. 87D



Oscillator No, 87G



Oscillator No. 87J



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Last revised: December 04, 2025
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