This circuit uses a contactor having been found in a 1987 publication. More modern equivalent devices may be used. The circuit has neon indicator lamps.
This low distortion circuit was found in a 1964 Electronic Design. The transistor admits...
Found in an Electronics Now from the 90s, this circuit can be triggered by an external control...
This range corresponds to the lowest TV channels, 2 and 3 specifically in VHF. The circuit is from...