This circuit is from 1975 documentation. Transistors such as 2N3055 can be used and the transformer is of a special type. R1 is 200 ohms and R2 is 10 ohms.
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...