This circuit for controlling high power LEDs (up to 2A) is from a General Electric documentation from 1970. The circuit serves to modulate a transmitter in PWM. The circuit serves as a shield.
In the figure we have a sensor circuit that makes use of common transistors and a photo diode as...
This unusual configuration, but which has already been explored in other articles, uses diodes in the...
This circuit uses a modulated signal from a PLL 567 to operate safely with an infrared emitter. The...