This circuit with pressure sensor was obtained from the Encyclopedia of Electronic Circuits volume 5 of 1995. Note the construction of the sensor with rubber and conductors.
Using power transistors of the time, this source was published in Radio Electronics magazine in...
Found in an American publication on transistors from the 60's, this circuit uses a transistor...
This circuit is from a very old publication, from the 60s. It uses germanium transistors from the...