Found in a 90s Popular Electronics, this mixer can be expanded to more channels. Transistors can be modern general-purpose equivalents.
This circuit is from an old French publication. With it we can have full wave control of a charge...
This is an improved version of the previous circuit also found in the December 1990 Radio...
This VCO with the 4046 PLL generates signals from 0 to 1.5 kHz. The circuit is from a Radio...