This General Electric circuit, in a documentation from the 1960s, allows the use of high resistance resistive sensors with unijunction transistors in a relaxation oscillator.
This circuit is from a 1995 publication; The current is obtained by dividing 1.25 by R1. The...
We found this circuit in an old American publication. It is possible to test common FETs using a...
This circuit was obtained in a 90s documentation from Analog Devices. The sensitivity is in the...