Diagram
N648
50v, 20v and 2.5v DC supply
6 inch gong
operating minimum voltage
Bell 48A - 2.5v
Bell 48B - 20v
Bell 48D - 50v
Bell 48C - Trembler bell, similar to Bell No. 48B, for preliminary signal in noisy
situations in PO buildings.
Twin 250 ohm coils
Uses Bell Gong No. 19 (cow gong)
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