In article
,
Andy Dingley wrote:
The old GPO way of arranging local ringing was a relay and mains
transformer to switch AC. You can find these sets on eBay. Another way
would be a hand-cranked generator 26, again easy enough to find on
eBay (tenner-ish, but watch postage as they're heavy).

Maplin used to do a ringer kit. Not Vellerman - one of their own. Worked
well - used it for theatre stuff. I've still got the circuit if anyone
wants it. Did UK and US ring intervals. Used a mains to 6 volt transformer
the wrong way round to get the volts from the oscillator.

--
*A clear conscience is usually the sign of a bad memory *

Dave Plowman London SW
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