This polarity inverter circuit for voltages down to about -12 V was found in the December 1992 issue of Radio Electronics magazine. The current is a few mA.
Found in American documentation from the 90s, this circuit can use a BC548 instead of the original...
This circuit acts on the dynamic range of an audio signal, which can be useful for recording,...
This circuit doubles the frequency of a signal using a varicap. In this case, the input is 28 MHz,...