This circuit was found in documentation from the 1980s. It is powered by the audio signal that must be cut. Transformers are the critical components and transistors are 2N2222.
This high input impedance circuit was found in American documentation from the 1980s. The power...
This circuit shows on the screen of an oscilloscope two signals alternately at a frequency that depends...
This circuit transmits the signal taken from a telephone line to a receiver placed nearby (up to a...