This circuit is from a 1966 Motorola Field Effect Transistors Manual. The circuit makes use of other components from the time. Modern equivalents can be tested.
The circuit shown has a voltage gain of 500 times and can use equivalent FETs like the BF245. The...
Found in a 1968 Novel Electronics Circuit, this circuit compares two light intensities using...
We found this circuit in an old publication from Argentina. The relay must be of the sensitive type,...