This circuit was found in an English publication from 1967. The circuit is for listening on a phone. Transistors are types of germanium of the time.
This simple circuit was found in an English magazine that no longer exists, January 1970 issue. This...
Using two common operationals, such as 741, this circuit serves as a medium control in an...
This circuit has a logarithmic response as a function of the light falling on the sensor. The...