We found this circuit with JFETs in a Radio Electronics magazine from June 1969. The circuit has its assembly described in a complete article. Equivalent transistors can be used.
Suggested by General Electric in 1965 documentation, this circuit controls the current at a load...
Found in Popular Electronics from the 1980s, this circuit uses two operational amplifiers from...
We found this circuit in a Hands-on Electronics from 1985. The circuit is based on common...