This circuit is from a 1965 Electronic Design. The transistors may be general purpose and the power supply must be symmetrical.
This circuit was found in a 1968 General Electric documentation. It has an input impedance of 2 M ohms...
Suggested by General Electric in a 1965 documentation, this circuit can use the TIC106 as an SCR....
We found this circuit in a 2004 documentation. The trimmer is common for 30 pF or 40 pF and the...