TELEPHONE No. 746 & 8746
VOLUME CONTROL AND UNICOIL BELL
Some later variants of the 746 and 8746 were fitted with a single coil bell called the Unicoil bell.  This bell could also be supplied with a volume control.
 
The above picture shows the Unicoil bell and volume mechanism.  The lever projecting from the front of the case, can be moved from side to side.  There is a spring attached to the lever (visible just above the bell plate) and this spring restricts the movement of the bell clapper arm.
 
The volume arm removed from the mechanism.  The restrictor spring is show centrally.

 
 
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Last revised: December 06, 2011

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