Found in a 90s Electronics Now, this circuit multiplexes audio signals for stereo transmission. The circuit is controlled by crystal.
An audio signal is applied to the input of this circuit. Depending on the position of the selector...
This circuit uses a dual floodgate MOSFET not very easy to obtain today. Its handling is very...
This crystal or galena radio uses a germanium diode. C1 is an old radio variable and L1 has 100...