This circuit triggers an alarm when the mains power is cut off. The circuit was found in the July 1990 issue of Radio Electronics magazine.
We show an oscillator that produces rectangular TTL signals based on inverters. Inverters can also be...
I got this circuit from a magazine in 1967. The magazine no longer exists, but the circuit that...
This egg timer has been found in an English magazine that no longer exists in 1982. The...