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Novice: Audio Activated Circuit

Novice: Audio Activated Circuit

Novice: Audio Activated Circuit

I'm a novice, I don't know much about electronics, but I'm enthusiastic and looking to learn....

I'm trying to find an audio activated circuit like one of those whistle key chains where a loud noise activates the circuit.  I've taken one a part, but there appears to be some sort of surface mounted small IC covered in black epoxy rather than mounted as a chip (four pins, no casing)

Any ideas where I could learn how to build a simple circuit like this, I'd like one that lights up when activated by noise instead of beeping.

Thanks in advance,

RE: Novice: Audio Activated Circuit

Go to Electronics Goldmine @ www.goldmine-elec.com and look up item# T7031. This is simple, striaghtforward and may serve your purpose.

RE: Novice: Audio Activated Circuit

Thanks for the lead... unfortunately, a search on T7031 at that site comes up blank.  I've also searched on 'audio activated' but nothing came up - how did you find it?  I'll have a good look through the site tonight when I get home.


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