A BPO wooden Bellset used with Telephone No. 4 on CBS No's 1, 2 & 3 systems and Repeater Telephonic No. 9A on CBS No. 1 & Magneto systems.

Fitted with a magneto bell ringer which has two 500ohm coils.  There are links (shown as "A" on the diagram) to the left of the bell that can be configured to make the ringer 1000ohm or 250ohm.

The Bell ringer is also ready to accept a bias spring.  Click here for more information on Bias Springs.

The housing is called a Case No. 1 and could be constructed of American Walnut, Black Chuglam, Pyinma, Halou, Tasmanian Myrtle or African Mahogany.

There were three revisions to this Bellset: Mark 1, Mark 2 and Mark 3.  The revisions are unknown.

Superseded by Bellset No. 31 in 1946 for new work, except when used with Telephone No. 1/194

Bellset includes (1928):-
1 x Bell No. 1A, unmounted.
1 x Bell-gong No. 2, Oxidized.

1 x Bell-gong No. 2A, Oxidized.
1 x Coil, Induction No. 1 or No. 12.
4 x Screws for fixing.

2 x Washers, Locking, 1-2BA.

Diagram - N505.

Drawing - 1576 (Dated 1913).

Adjustment of Magneto bells

Click here for the difference between a Bell and a Bellset

Bellset No. 5 internal view - the gongs are black!
Picture dated 1929
Paster diagram from a GEC produced Bellset
Bellset No. 5 Mark 3


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Last revised: July 19, 2022