The two circuits shown show how to obtain an SSB / CW control for receiving this signal top at a common receiver. The circuits were found in an old American manual from the 80's.
This circuit triggers a buzzer or other warning device when the light falling on the sensor is cut...
Great sensitivity for the circuit can be obtained with a Darlington amplification step for the...
Suggested by Sprague in the 1980s documentation, this circuit can control three-phase AC motors....