Suggested by Mullard in an old documentation, this circuit is based on a common phototransistor and on transistors that may be the modern BC548.
This circuit provides a power of 12 W with 24 V of supply, consuming a current of 820 mA and...
This circuit is from 1976 documentation, but it can be assembled with more modern transistors like...
In the figure we have the way to implement a logic gate or (OR) with an LM393. The circuit must be...