Found in a 1980s American documentation, this circuit can use a SCR and a general-purpose transistor. R2 is 1 M and R1 is 10k. The capacitor is 47 uF.
In the figure we have a high input impedance stage with a general purpose PNP transistor. An NPN transistor...
We found this circuit in documentation from Ferranti from 1968. The circuit uses transistors from that...
This thermometer, which uses common diodes as sensors, was found in a 1975 magazine -...