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By mramos1
#15433
I have heard there is a unit that will detect fire and police and light an LED for deaf drives.. I have googled all over. Nothing. I think US sirens are in the 1-2Khz range.

Has anyone done anything like this or have a circuit similar. I want to mount a mic outside the car, and light an LED in the car, direction is not important.

I am weak in analog/filters. And I know some of you guys will spice it in seconds. I can get more details if needed. It would be nice it all discretes over
an op-amp as well, but begger can't be choosers.

Thanks.