This circuit was found in a 1967 General Electric manual. It shows a SCR control with unijunction and zener diode. The triac depends on the controlled load.
This circuit is valid for 106 series SCRs and can be modified to operate on the 110V power grid....
Found in an October 1992 Radio Electronics magazine article, this circuit generates a low-power tone in...
This circuit was obtained in a Popular Electronics of the 90s. The circuit is compatible with...