TELEPHONE MANUFACTURING Co. (TMC)
TELEPHONE S528623 - Type 851


Table telephone Type 851 (S528623)

The telephone is plastic cased with hard wired internal components.  The bell consists of one oblong gong which sounds like a cow bell.

The dial looks solid but the inserts in the finger holes are spring loaded and are pushed in by the finger.  The dial still needs to be rotated.

The base does not have feet as such and has a rubber mat glued to the base.  These tended to deteriorate over age.

The telephone has a circuit the same as standard GPO 700 series telephones.  Even though this model does not have a regulator it is wired for one.  In place of the regulator are two resistors on a circuit board coded S528669, which is held in place by 5 screws.

This telephone can be converted to work on the UK plug and socket system - Wire as a Telephone No. 706.

Wiring diagram - S28674.


 



 



 


Rubber mat instead of feet
 



 


Dial mechanism

 

Circuit diagram
Click on picture for an enlarged view

 

 

 
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Last revised: January 07, 2023

FM2