From: dmn@kepler.unh.edu (There's a seeker born every minute.)
Subject: flash LEDs with sound?
Organization: UTexas Mail-to-News Gateway
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     I'm looking for a circuit that will flash an led on in response 
to the output from a walkman cassette player. How could I do this?
I don't want it just to turn on, I want it to 'strobe' once so to speak,
per every beep I put on a cassette tape. 

     Would it be better to use a circuit based on the volume of the beeps
on the cassette, or better for the leds to respond to a tone of a certain
frequency? Is there any easy way to do either of these? I'm looking for 
the simplest circuit possible. I guess what I'm asking for is some sort of
color organ, but not quite. Let me trt to explain again...


     I'm going to have a pattern of beats (or beeps) on a cassette tape.
So on the tape you'd hear:   beep! (pause) beep! (pause) beep! (pause)..etc. 
, with speed increasing as time goes on. I want to synchronize an LED (
probably two of them) with the beeps on the cassette tape. So the LED, with
each beep, would go on and off real quick, generating a strobe light sort
of effect. The rapidity of the beeps on the tape would in turn effect the
rapidity of the blinking of the LEDS. And if there was no sound on the tape
(except for background his), the LEDs would remain off. Please help!


  Thanks,

    Dana