Mechanism No. 13

Early A and B coin recognition mechanism.

Note the buttons are actually labelled A and B and early casings had no A and B markings on them.  The GPO soon realised that people were not seeing the letters on the buttons and quite early on marked the casings with A and B in white paint.

This mechanism was superseded by the Mechanism No. 14 which had a small row of connectors to the lower right of the mechanism, instead of the large brass studs.

The pictures below were all dated 1926.

Front view of the mechanism
The brass connectors are to the left, the timing mechanism can be seen centrally and the coin gong can be seen to the top right of the connectors.
Sideways view of the mechanism showing the coin transmitter (the bell shaped object to the upper left).  This mechanism differs from the one above and is possibly an early prototype.
Close up showing the brass bullet connectors on the mechanism and the connector strip on the back of the coin box.
Extreme close up of the connector strip
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Last revised: December 11, 2017