Found in American documentation from the 1980s, this circuit has a diode feedback. At the exit we have an indicator LED. The LM3900 is a transconductance operational amplifier.
The output voltage of this unit is approximately 1.4 V less than that of the chosen zener. The...
Found in the April 1980 issue of Radio Electronics magazine, this stage uses transistors from the...
To control direct current loads, under voltages between 12 and 200 V, and currents up to 3 A, we...