Variable Tone Siren (CB495)

This siren uses a antique 2N2646 unijunction transistor and a 555 IC to produce a modulated tone. Adjustments are made by the potentiometer and the signal can drive a small loudspeaker or ceramic transducer. If you want more power you must add a power audio stage.


Variable Tone Siren
Variable Tone Siren



Circuit Bench

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