Found in a Popular Electronics from the 90s, this circuit uses common components with several operational options, including the use of an optocoupler that allows its application in a shield.
This nonlinear gain circuit was found in a 1965 Electronic Design. The configuration can be used...
This circuit adds an amplifying transistor that can supply loads of up to 250 mA. The circuit is...
I found this circuit in a 1992 Electronics Experimenter Handbook. The circuit can be easily...