BELLSET No. 41


Wooden cased Bellset with Bell No. 1A, capacitor, two rectifiers and a relay.  There is no induction coil.

Used with Tele No. 310 on shared service separate metering.

This Bellset CANNOT be used in place of a Bellset No. 1 or Bellset No. 25, because the Bellset No. 41 has no induction coil.  It can, however, be used as an extension bell.

This Bellset was used on Party Lines to stop bell tinkle on one of the users, when the other user dialled out.  The unit incorporated a full wave rectifier bridge and relay, in a manner that the bell was connected once a burst of ringing current was received.  As the relay was slugged (to be slow to operate), it did not respond the the spikes caused by dialling.

In 1947 the Thermistor was invented and this was a miniature device that effectively made the Bellset No. 41A redundant, as the Thermistor could be incorporated into any size of phone.  The Thermistor was used to stop bell tinkle.

Adjustment of Magneto bells

Click here for the difference between a Bell and a Bellset


How to wire a Bellset No. 41 as an extension bell

  1. Remove links 8 - 9 and 6 - 7.
  2. Connect a 3.3K resistor between terminals 7 and 8.
  3. Connect white of the line cord to terminal 7.
  4. Connect Blue of the line cord to terminal 9.
  5. Insulate the red and green wires of the line cord.  These are not used.

 

 

 
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Last revised: February 01, 2015

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