In this circuit of an American documentation of the 90s, when the light is cut, we have the production of a pulsating tone. R3 determines the trigger sensitivity.
Found in an American documentation from 1968, this circuit senses the temperature through an...
This circuit is intended to trigger an alarm when the input voltage exceeds one value and to...
This 80's amplifier delivers 6 W of 8 ohm speaker power without using an output transformer....