warbler siren

Posted on Aug 11, 2012

This circuit provides a good siren noise suitable for warding off robot-predators! Change the pitch by adjusting R2, and R5.

Click here to download the full size of the above Circuit.

all resistors are 5 or 10 percent tolerance, 1/4-watt all capacitors are 10 percent tolerance, rated 35 volts or higher

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