Every so often I find myself buying products just to find out how they work... Recently I bought a cheap battery powered Piezo alarm...very small and quite loud...
(I believe it's sweeping btw. two frequencies to be even more
audible...so it's probably a piezo transducer.)
I'm looking for help in figuring out how they made it so loud.
(The audio jack is being used as a switch...alarm goes on when
pin is pulled out...pin is stopped from coming out via housing...nice hack)
I will draw up a schematic soon... here some pics
Unfortunately I've never seen the critical part in question (black with 3 pins).
I'm guess I'm looking at a transformer? inductor?
Can anyone give me hints towards reading material or electrical tests I can do to find out more...
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