This QST circuit generates 4 frequency signals according to the crystals used. Transistors admit equivalents although the indicated types can still be found with some ease.
This circuit was found in an old documentation and can be powered by a solar panel. The touch...
This simple circuit can be used on both 110V and 220V mains. We find it in an 80's Electronic...
This circuit was found in a 1980s instrumentation publication and can be applied to virtually any...