Found in Popular Electronics from the 90s, this circuit consists of a timer that turns off the power of a circuit after a time determined by C1, saving the battery.
In the figure we have a simple amplifier stage with a temperature compensated general purpose...
This full-wave dimmer with SCRs was found in General Electric documentation from 1965. The circuit...
This is a battery powered 3W power amplifier using germanium transistors. The circuit is from an...