We found this circuit in a 1964 Electronic Design. The triac and SCR can be replaced with modern equivalents according to the load. The circuit is for 160V network.
This circuit, from the 90's, is intended for operation with vinyl record players of the time, as...
Using a zener diode it is possible to change the linearity of the scale of an analog instrument by...
Found in American documentation from the 1980s, this circuit prolongs the ringing of a doorbell or chime...