This circuit was obtained from the Encyclopedia of Electronic Circuits volume 5 of 1995. The circuit uses the 4001 CMOS to obtain hysteresis in the sensor feedback.
This circuit was found in old documentation. The SCR can be any of the 106 family. Note the sensor...
This circuit was found in Ferranti's 1974 transistor manual. The transistors are from the period and...
Short duration pulses can be obtained with the relaxation oscillator that uses common transistors and is...