This circuit, suggested by an Electronics World of 1969, keeps a blinking LED for a while when a power outage occurs. Time depends on capacitor C1.
The purpose of this circuit is to provide a constant current to an experimental electromagnet. The...
This Headset Coupler or Phone Patch was found in an American 1980s amateur radio documentation. The...
This small circuit for the medium or short-wave range, depending on the coil, was found in a...