BELLSET No. 31


Bellset used by the BPO on Direct Exchange Lines with Telephone No's 156LB, 196LB or 246 in L.B. exchange areas.  Also used on CBS Exchanges No's 1, 2 & 3.

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 CBS No. 1 (Diagram N1296) and CBS No's 2 & 3 (Diagram N1297).

Superseded the Bellset No. 21.

Colours:-
Black - For use with Telephones, Nos. 156LB, 196LB, 1/196LB and 246.
Jade Green, Ivory and Chinese Red - For use with Telephones, Nos. 196LB and 1/196LB.

Bellset includes (1946):-
1 x Bell No. 59A, Unmounted.
1 x Bell-gong No. 2, Nickelled.
1 x Bell-gong No. 2A, Nickelled.
1 x Clip No. 29.
1 x Coil, Induction No. 21.
1 x Condenser, M.C., No. 102.
2 x Parts, No. 2/SSC/17.
2 x Parts, No. 1/SSC/338.
1 x Parts, No. 1/SGU/1 (Colour).
1 x Parts, No. 1/SCO/1 (Colour).
2 x Washers, Locking, No. 1210.

Bellset includes (1956):-
1 x Bell No. 59A, Unmounted.
1 x Bell-gong No. 2, Nickelled.
1 x Bell-gong No. 2A, Nickelled.
1 x Clip No. 29.
1 x Coil, Induction No. 21.
1 x Capacitor, Paper No. 7705.
2 x Parts, No. 2/SSC/17.
2 x Parts, No. 1/SSC/338.
1 x Parts, No. 1/SGU/1 (Colour).
1 x Parts, No. 1/SCO/1 (Colour).
2 x Washers, Locking, No. 1-2 BA.


Diagram - N531.

Drawing - 63034.

Specification - S90.

Adjustment of Magneto bells

Click here for the difference between a Bell and a Bellset

How to spot a reproduction Bakelite Bellset cover

Covers and dimensions

Internal view of the Bellset
Capacitor to the left and Induction Coil to the right
 


Bellset No. 31 wiring diagram

 
 
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Last revised: December 09, 2022

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