Quote:
Originally Posted by Dave Moll
The magneto would probably be a general purpose one, and that contact may be used in other circuits. For instance, in the GPO magnetos I mentioned in an earlier post...
|
The 'Magneto 26A' used since about 1940 was not only used in LB telephone circuits, but was used in the Beethoven shot-firing exploder where the 'close-on-turn' contact was configured to good effect. I agree that the magneto in the OP telephone would have been manufactured with the contacts configured for 'economies of scale'. This was an established practice with GPO telephones in any case: interchangeability of parts on economy grounds.
Quote:
Originally Posted by Dave Moll
It looks as though it would be possible to wire your 'phone so that this contact would disconnect the local ringer while the magneto is cranked if you didn't want it ringing while you crank.
|
A glance through H. G. White's 'Telephone Erection and Maintenance' of the 1920s reveals that 'Silent ringing' was an option for this type of telephone, and that local bells ringing was not unusual, although the telephone described in the book had the bells in series with the magneto and was restricted to short lines of less than ten miles. No mention of bells permanently shunted across the line (like on the TAI-43).