We found this circuit in the Radio Electronics magazine of May 1977. The transformer voltage is 6 + 6 V, and the current depends on the zener diodes and is in the order of 100 to 200 mA.
This circuit was found in a Radio Electronics from May 1965. FETs are from the time, but the...
This circuit can generate signals from 80 to 800 Hz with an amplitude of 0.3 V. We find it in a...
Because it uses TTL integrated circuits, this siren must be powered by 5 V or as indicated with D1 to...