This amplifier was found in a 1957 Rayrtheon documentation. The circuit can be fitted with a BC558 transistor. Driver and output transformers can be obtained from unused transistor radios.
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...