The circuit shown was found in a 1967 RCA manual. Modern equivalent components can be used. The SCR must be according to the controlled load.
Found in a 90s QST, this circuit uses an operational amplifier that is still common. It generates...
This circuit was found in a publication of the year 1968. It uses complementary transistor to...
This circuit is from a 90s Popular Electronics. The circuit employs a ZN461E that is not a common...