This control circuit using a low voltage switch was found in the September 1987 Radio Electronics magazine. The triac must be matched to the load and the mains voltage.
This simple signal injector oscillator was found in a 1981 documentation. The coil can be made...
This variable oscillator was found in a Mullard transistors manual from 1960. The resistor R5 is...
This circuit is from an American 80's documentation. The circuit indicates when the voltage of a 9 V...