This circuit was found in a 90s Popular Electronics. The circuit uses several relays in order to obtain different controls for power loads.
This amplifier stage was found in a 1956 Sylvania manual and has an unusual configuration with a...
This circuit for incandescent lamps is from a publication from the 70s, but it can be assembled with...
This filter is from 1978 documentation. The source must be symmetrical and the gain in the center of...