This circuit was found in a 303 Circuits issue of Elektor magazine from the 1990s. The circuit uses an equivalent operating system. The source is not symmetrical.
The flashing LEDs in this circuit simulate a working alarm and can serve as a deterrent to a...
This circuit is from an April 2000 Poptronics. The magazine no longer exists, but the circuit can...
Found in a Popular Electronics from the 90s, this circuit presents the difficulty of obtaining the...