Jack Unit No. 1A and 1B


Jack Unit No 1A and 1B are generally used in conjunction with a Telephone No. 713 and a Mounting Dial Automatic No. 21.  A handset or headset can be plugged into the socket, which is a Jack No. 84A.

The unit comprises of a telephone circuit similar to that of any 700 type telephone, except that it obviously does not have switch hooks, handset or a dial.

The Jack Unit No. 1A has the circuit board mounted sideways to the base and uses the plug in Regulator No. 1.

The Jack Unit No. 1B uses the Telephone Unit No. D93039 as the main circuit board and is fitted with a Regulator No. 6B.

Generally, these were used on Key and Lamp units, exchange supervisors desks etc.

Jack Unit No 1A introduced 1963 and the Jack Unit No 1B introduced 1973.

Drawing - 91611 (No 1A)
Drawing - 93288 and 93290 (No. 1B)

Diagram - LD 178 (No. 1A)
Diagram - SA/SAW 9228 (No. 1B)

Jack Unit No. 1A (1963)
Internal view
 

Jack Unit No. 1B (1973)
Regulator No. 6B is not fitted
Internal view
 

Jack Unit No. 1B (1973)
Regulator No. 6B is not fitted
Internal view

 

 
 
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Last revised: April 13, 2022

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