BELLSET No. 7
Wall mounted switch unit for extension plans 5 & 7 on CBS No. 1 systems and
fitted close to the main telephone.
For 1 exchange line and 1 extension with intercommunication, with or without secrecy.
Wooden construction with ringing generator, four position switch, indicator and magneto bell.
Introduced in 1923.
Diagram - N507.
Bellset includes (1928):-
Bell set No. 7 interior
Last revised: April 29, 2020