This mono circuit for 10 LEDs was found in the January 1991 Radio Electronics magazine. It is powered by 12 V.
This very simple circuit must use coal microphones of the type found in very old equipment. The...
This biestable circuit was found in a Popular Electronics from the 90s. The circuit has an unusual...
This circuit was found in a 1969 US documentation. It provides a signal that can be externally...