Sound Activated Switch

[tbank]

Hello,

I am looking for a schematic for a sound activated switch with a variable delay until switching off. This circuit will be used to activate an ultrasonic dog whistle to discourage barking...however, the clap circuits I have seen require an additional clap to turn off. I don't want my dog to get the whistle stuck on as a result of not barking (clapping) enough times. Thanks.

 

[hsvgtsr1]

i have circuit similar to what you want. you have to give me a couple of days to draw it up an i will email it to you

 

[bogdanfirst]

how about these?
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[Fred jacob]

This could be useful for solving my problem

 

[JimB]

how about these?

Looks like four dead links in a 17 year old thread.

A candidate for locking I think.

JimB