TELEPHONE No. 73
This was a modified Telephone No. 21, used on long distance private wires.

Circuit diagram - N173.

Circuit diagram - CBS 48.

Found in the 1914 and 1915 Rate Books.

Original date of circuit diagram N173was 28th March 1917.

Telephone included (1914 and 1915)
1 x Coil, Induction No.1.
1 x Cord, Flexible No. 22.
1 x Receiver, Bell No.1.
1 x Transmitter No. 1 (Mark 236).

 

 
 
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