My grandmother's door bell stopped working (one that's mains powered,
via a "hard of hearing" box which also makes a series of lights flash in
her house), so I bought a new "mains powered" 8V bell from B&Q. It
doesn't work properly though; it rings once when you press the button
in, and once again when you release it. I'm guessing the bell wants AC
but is getting DC. It doesn't say on the packaging or the instructions
whether it wants AC - only "8V 1 amp". Are most mains powered bells AC?

The old one was designed to be battery powered by two 1.5V "D" batteries
and the electrician who fitted the "hard of hearing" box and flashy
lights just replaced the batteries with a cable from there, so I guess
it could have been more than 3V and it burned out after a few years.
Sadly I can't find my multimeter to see what it's actually outputting.

alex.

--
Alex Meaden
Technical Support Officer
Computing Service
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