Wanted: Identification of artefact

[Chris Suslowicz]

Ah, the mistake was using the voltmeter on the DC ranges. The magneto generator in a field phone typically puts out 70 - 120 volts at around 19Hz (voltage and frequency will depend on load and how fast you crank it).

It's enough to give you quite a 'belt' if you're not expecting it - or even if you are.

It may be an accessory for early switchboards that used buzzer calling to allow them to be used with magneto telephones. (Or just to ring a bell (or bells) somewhere, e.g. on a rifle range.) The sockets are probably for standard 1/4" jack plugs (2 conductor type), as used of Switchboard U.C. and earlier types.

Best regards,
Chris.