This circuit is from a 1924 book by Gernsback. The receiver uses two tubes and listens to headphones. Power is supplied by battery with the indicated voltages.
This simple circuit, based on an astounding 555, was found in a 2001 documentation. The circuit...
This circuit generates sinusoidal signals that depend on the input oscillator. The circuit is from...
This is one of many power control or dimmer configurations that we have found on this site and in...