BELLSET No. 31
This Bellset was similar to the Bellset No. 26 except it also contained a Coil, Induction No. 21.
Used when a local battery, to power the telephone transmitter, was required.
The Bellset is usually wall mounted and the cover was produced in plastic in the colours black, red, green and ivory. The early covers were replaced circa 1963 with a thinner plastic cover coloured grey or ivory.
The early covers were Part No. 1/SCO/1 Colour, the black being produced in Phenolic Resin, Type GX (Specs BS771 & S116) and the three colours in Diakon, Grade L.A. (Spec S116).
Grey and Ivory covers were called the Cover No. 71A (Colour). They were made of Toughened Polystyrene Type 1 (Specs BS3126 & S116).
The early cased bell sets could be fixed under a 100 or 200 type table telephone. Special fixing screws are required which supplied as standard on the earlier bell sets. A Cord, Instrument No. 4/51H, Brown, 9" or Cord., Instrument No 5/22H, Brown, 9" would also be required.
Some of these Bellsets were produced by ATM.
Generally used in exchange areas working on:-
Superseded the Bellset No. 21.
Bellset includes (1946):-
Bellset includes (1956):-
Drawing - 63034.
Specification - S90.
Internal view of the Bellset
Bellset No. 31 wiring diagram
Last revised: March 16, 2023