Leak Detector (CB22456E)

We found this circuit in a Popular Electronics from 1992. The transistor is general purpose, assuming equivalent.

Monostable 4013 (CB4604E)
This circuit uses one of two D-type flip-flops available on an integrated circuit 4013. The...
High stability thermocouple amplifier (CB4942E)
This other high stability thermocouple amplifier uses an 80's operating. The circuit can be used...
SCR manual control (CB8148E)
This circuit was found in a 1967 General Electric manual. It shows a SCR control with unijunction...