Based on Radio Shack 276-137, this circuit was found in the December 1995 issue of Electronics Now magazine. The circuit drives an LED but could use a relay instead.
In the figure we have the shot made by an interrupted light beam using a phototransistor or a...
Using a CA3130 operational amplifier, this circuit from a 1977 documentation can handle low...
This is the receiver for the CB1364E transmitter. Other receivers can be found in this section of...