This circuit is an alternative to the previous circuit. We found it in the same article in the Radio Electronics magazine of March 1992. The integrated circuits are the LM3914.
This highly sensitive light sensor was found in a 1970 General Electric documentation. The circuit...
The given number circuit is used to activate the relay by interrupting the light beam that hits...
This alarm circuit with sensors in series was found in the Electronics Now magazine of June 1994....