Wall mounted, C.B. telephone, with a press button switch used as an extension telephone in conjunction with a Telephone No. 5, giving intercommunication.

Previously known as the "Telephone, Wall, C.B. with rotary key".

For "Secrecy" the links in the telephone should be connected between 1 and 2 and for "Non-Secrecy" between 1 and 3.

This telephone calls the Main Set by intermittently earthing the B line by means of the Rotary Key. This operates the Biassed Bell without indicating a signal at the Exchange.

This was the wall equivalent of the table model, the Telephone No. 10.

Telephone includes:-
1 x Hook, Receiver F.
1 x Switch, Receiver No. 2.
1 x Coil, Inductor No.
1 x Bell No. 1A, Unmounted.
1 x Condenser, M.C., No. 18.
1 x Transmitter No. 1.
2 x Cord, Flexible No. 116.
1 x Cord, Flexible No. 222.
1 x Receiver, Bell No. 1.

Circuit diagram - N107 (dated 1917).

Circuit Diagram - CB140A.

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Last revised: July 03, 2024