CW tone generator (CB21673E)

This telegraphy circuit generates an audio tone from a pure RF carrier. We found it in a publication by Gernsback from 1960.

Fast Photo Darlington (CB14647E)
With the circuit shown, you can have a fast response with a Darlington configuration. The circuit is...
Thermostat (CB24644E)
We found this multiple thermostat circuit in July 1980 Radio Electronics magazine. It uses...
EF MOSFETs Series with Diodes Fast Body (COM042E)
Mouser Electronics is already providing new MOSFETs EF SIHx28N60EF of Vishay series for voltages...