Found in a 90s Popular Electronics, this circuit uses a MAR-X to amplify signals up to 2 GHz. The circuit is quite critical.
This Japanese commercial transistor radio circuit was found in a 1967 documentation. The...
This TTL oscillator uses an old TV crystal, having been found in an American publication in 1976....
This simple circuit indicates when the two channels of stereo equipment are balanced. The diodes can...