Based on a unijunction transistor, this circuit was found in the January 1994 issue of Electronics Now magazine. The frequency range depends on C1, which can be changed.
This circuit is from a Radio Electronics magazine from July 1984. The transistor determines the...
This circuit was found at Electronics Now. It can be used as a shield detector for dial signals in an...
This circuit was obtained from an English circuit manual. Components are common and LEDs can be 3...