BELL No. 48

DC Trembler bell for use outdoors with 6 inch gong (Bell-gong No's 9, 15 or 15A).  Fitted with components to suppress radio interference.

Operating minimum voltages
Bell No. 48A - 2.5v (2 x 12.5 ohm coils) - Used for quarterly peg counts.
Bell No. 48B - 50v - (2 x 250 ohm coils)
Bell No. 48C - 50v - (2 x 250 ohm coils)
Bell No. 48D - 50v - (2 x 250 ohm coils) - Superseded Bell No. 48B in 1975.

Bell No. 48C - similar to Bell No. 48B and used for preliminary signal in noisy situations in PO buildings.  This bell uses a Bell-gong No. 19 (cow gong) and has terminal connections, located above the coils, which allow the coils to be connected in series or parallel.

The Bell No. 48B contained a Capacitor MC No. 101 whilst only provision was made within the case of the Bell No. 48D for a Capacitor MC No. 101 to be fitted subsequently.

Radio Suppression Components:-
2 x Capacitor No. 8001.
1 x Capacitor No. 8003.
2 x Inductor RF No. 15, 1 Amp.
1 x Resistor, Carbon No. 26GC 100ohm.

Width - 6.5 inches.
Height - 13.75 inches.
Depth - 9.5 inches.

Drawing - No. 92190 (Mark 2).

Diagram - N648.

Specification - S199.

Bell No. 48B Bell No. 48C


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Last revised: July 11, 2022