We found this circuit in an American documentation from 1975. The list of transistors that can be used is attached to the diagram. Modern types can be experienced.
We found this protection circuit for the power supply in a 1992 documentation. This circuit has...
I found this circuit in a documentation for radio amateurs from 1975. The FET could be the BF245....
Found in an American 80's documentation, this circuit can use common FETs like the BF245 and cover...