BELLSET No. 4


For C.B. Intermediate CB switching Bellset with 4 position switch.

Introduced in 1909 and used on circuits with one exchange line and one extension giving intercommunication with or without secrecy.

Used on extension plans 5 & 7.

Superseded by Bellset No. 20.

Bellset includes (1928):-
1 x Bell, No. 1A unmounted (with Bell gongs No. 17).
1 x Condenser, M.C., No. 14.
1 x Generator, No. 4C.
1 x Indicator and key, No.1 (for mark 234) or No. 4 (for mark 235).

Diagrams
Circuit - N504.
Mark 234 - C.B. 607 and 608.
Mark 235 - C.B. 877 and 608.

 

 
 
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Last revised: January 27, 2020

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