We found this circuit in an American documentation from the 80s. In it we have the way to control the amplifier gain by an input voltage.
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...