This amplifier step for small signals can use any general-purpose transistor like the BC548. The circuit can be powered by voltages from 6 to 12 V.
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...