MECHANISM No. 20
This is a Pay on Answer (POA) mechanism and is fitted to Boxes Coin Collecting No. 700 and 705.

This mechanism differed from the earlier A&B ones as the user inserts coinage once the call is answered and not before.

The spare mechanisms are transported in a Case No. 206.

Testing a Mechanism No. 20

Operational Sequence charts - 91194/1 and 91194/2

E.I. Telephones, Call Offices D5511 - Parts available

Drawing - 92546.

Specification - S978.

Front view of mechanism Rear view of mechanism

 

In the picture below the coin runways have been removed to expose the mask

 

 

 
 
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Last revised: July 29, 2026

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