TELEPHONE No. 4

Standard CBS No. 1 table telephone if used with Bellset No. 5.
Standard CBS No's 2 & 3 table telephone if used with Bellset No. 15.

Fitted with Transmitter No. 2 and insert No. 3.  This transmitter could be rotated, to stop the carbon granules from packing.  Packing was a well known fault with fixed transmitters.

There was also a Telephone No. 4A that was used on Phonogram and Telephone-telegram circuits.  This had a plug ended (Plug No. 401) and a 4 wire line cord instead of a screw type block terminal with six wire connecting cord.

This was the standard telephone instrument arranged for standing upon a table.  Since this telephone is simply a transmitter, a receiver, and a gravity switch, the instrument is not complete, and a separate  hand generator is provided, usually fixed to the desk or table in close proximity to the table telephone; the induction coil and magneto bell, with the condenser (should one be required), are fitted in a case and are known as a Bell Set.

The bell set for use with the telephone is Bell Set No. 5, if the condenser is not necessary, and Bell Set No. 15 if a condenser is required.  The bell set need not be fitted close to the telephone so long as it is within audible distance of it.  The primary battery is placed in a battery box and fitted close to the bell set to which it is connected.

Telephone includes (1928):-
2 x Cords, instrument, No. 116.
1 x Cord, instrument, No. 222.
1 x Cord, instrument, No. 608.
1 x Hook, Receiver, F.
1 x Strip, flexible cord connection, 6-terminal.
1 x Transmitter No. 2.
1 x Receiver, Bell, No. 1A

To be requisitioned separately if required:-
Label No. 78, or 78C, or 78D.

Telephone includes (1946):-
1 x Block, Terminal, No. 20/8, Black.
1 x Dial, Auto., Dummy, No. 4.
1 x Hook, Receiver, F.
2 x Cords, Inst., No. 1/16E, Black, 12".
1 x Receiver, Bell, No. 1A.
1 x Transmitter No. 22.
1 x Cords, Inst., Nos. 22/22B, Brown, 33".
1 x Cords, Inst., No. 6/08A, Brown, 72".

Circuit diagram - N104.

Diagram C.B.S. 265.

Diagram No's 9544 & 62901.

Made obsolete in 1947 and superseded by Telephone No. 156LB.

See also the Telephone Efficiency Committees Report on Local Battery Area telephones.

Last revised: February 03, 2020