This old 4-channel circuit was found in the December 1994 Electronics Now magazine. The circuit uses a 556 as a modulator. Note the code programming key.
We found this circuit with several types of sensors in a 1995 documentation. The circuit also has...
This sensitive passage alarm was found in the August 1971 Radio Electronics magazine. The light...
The lighting sequence of the LEDs on this circuit, found in a 2001 documentation, is determined by the...