This circuit can modulate a laser rate at frequencies of 50 kHz. We found the old documentation. The bipolar transistors can be the BD135 and 136 and the FET admits equivalent.
This 3V-only circuit was found in old American documentation, but can be implemented with...
The output voltage of this circuit, which can regulate the current in a load between 0 and 1 A,...
This circuit was found in a Popular Electronics from the 90s. The circuit has temperature...