This circuit was found in a 1970 IEEE publication. The circuit functions as a voltage controlled variable resistor and can be used with audio signals. Transistors admit current equivalents.
This circuit using an operational amplifier was found in old American documentation. It can be...
Sound waves applied to the printed circuit board corrosion tank can speed up the process. The idea...
We found this circuit in an old magazine 73 of 1974. The circuit must be powered by a continuous voltage...