The circuit presented is a Japanese commercial radio for AM with 50 mW of output power, powered by 9 V. The circuit is from the 60s, having been found in documentation of the time.
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...