No. 329
Table telephone in, black moulded Bakelite case, fitted to a Bellset.
Probably used on Private Automatic Exchanges. The telephone has a two
position resistor card which is wired across the transmitter.
How to convert to PST
- Disconnect the red and white wire from the capacitor (the grey square component
in the Bellset) and insulate the end of the wire.
- Connect a 3k resistor between L1 and E terminal block (remove any wire
strap, if found).
- Connect the white lead of a standard telephone line cord to L1.
- Connect the red lead of a standard telephone line cord to L2.
- Connect the blue lead of a standard telephone line cord to C.
- Insulate the green lead of the telephone cord.
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| Front view of telephone |
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| Internal view of telephone and Bellset - not
the resistor card, just above this text |
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| Telephone Circuit Diagram |
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