Flash Signal Alarm Circuit

Posted on May 19, 2012

This circuit is useful if you need a low-energy flashing alarm. The 200 to 400-dc supply should have enough internal resistance to charge the 0.5 capacitor between flashes, about 2 or 3 time constants, which means about 500 kQ to 1 for a 1-s rate.

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

Use lower values for higher rates.

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