This source for 50 W amplifiers per channel was found in 1967 Delco documentation. Transistors are from that time, difficult to obtain today.
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...