TELEPHONE No. 81


Special fire telephone used in exchange buildings	This is the later model called the Mark 4

Fire emergency phone for use in CB and Automatic telephone exchanges. These were used to call the Fire Brigade and went via the area operator suite.

The Mark 1 was probably used by the National Telephone Co.

The Mark 4 version consisted of a Telephone No. 232 mounted on a Bellset which in turn is mounted on a wooden box that houses batteries and a hand generator. The hand generator is locked by means of a releasable metal bar.

The Mark 4 was introduced in 1938.

Telephone included (1928):-
1 x Bell, Magneto 1000w.
1 x Coil, Induction No. 3 or No. 14 .
3 x Condensers, M.C. No. 1.
2 x Cords, Instrument No. 116.
1 x Cord, Instrument No. 222.
1 x Frame, Notice No. 1.
1 x Generator N.T. No. 1001.
1 x Key, No. 72, red.
1 x Key-mounting V.
1 x Receiver, Bell No. 1A.
1 x Transmitter N.T. No. 13.
1 x Transmitter No. 1 and Adapter, transmitter, if used for maintenance.

Telephone included (1946 and 1956):-
1 x Bell-set No. 26.
1 x Glass No. 3.
1 x Cap, Lamp No. 2-1C.
1 x Jack, Lamp No. 10.
1 x Clip No. 31.
1 x Key No. 72, Red.
2 x Condenser, M.C. No. 102.
1 x Key-mounting, V.
1 x Cordage, Instrument No. 2/B, Brown, 18".
1 x Relay No. 503A.
1 x Relay-cover, AK.
1 x Frame, Notice No. 1.
1 x Telephone No. 164, Black, with Cord No. 3/63KB, 33".
1 x Generator No. 26A with adapter, generator, D 63018 and Handle, Generator No. 15 (earlier supplies fitted with Generator No. 8A).
1 x Telephone No. 1/232CB, Incomplete (minus Base, Telephone No. 1/162).

To be requisitioned separately as required:-
3 x Cells, Leclanché DS 5
1 x Lamp No. 2- ... V.

Circuit diagram - N181 (GPO).
Circuit diagram - N181 (NTC)
Circuit diagram - C.B. 1185.

Drawings - 63018/1 and 63018/2 (Mark 4).

Specification - D1299.

Adjustment of Magneto bells

Telephone No 81 (Mark 4)