This power control for powers up to about 10 W uses wire potentiometers in an arrangement that allows to maintain the impedance. The circuit is from old European documentation.
I got this circuit from an English magazine from 1977. It can still be easily assembled, as the...
This simple lie detector was found in Popular Electronics. Transistors are commonly used. The...
Found in a 1980 documentation, this circuit drives a transducer (X1) when the car battery has its...