This circuit was found in General Electric documentation from 1968. The circuit uses triac from the time as well as transistors that can be replaced by modern equivalents.
This circuit is from old documentation. The operational amplifier is uncommon nowadays. The...
This instrumentation circuit was found in the September 1989 issue of Radio Electronics magazine....
This JFET amplifier was found in documentation from 1958. The circuit has voltage gain of 4 and 10...