This circuit is from General Electric from the 80s, using a relay with high current contacts (20 A). The transistor admits equivalent, and any phototransistor can be used as a sensor.
The circuit we present is suggested by Linear Technologies (www.linear.com) and makes use of an...
This circuit for audio signals was found in the March 1990 Radio Electronics magazine. The circuit...
This modulated transmitter for a light beam communication system was found in the 1991 Electronics...