We found this circuit in a 1980s documentation. Equivalent components can be used. The circuit senses temperatures in the range of 0 to 50º C and uses a transistor as sensor.
Obtained from a 1967 documentation, this circuit uses transistors from the time. The galvanometer can be a...
Motors up to 2 A can be controlled by this circuit, which requires a symmetrical source. Although...
This sensitive MW receiver was found in a publication of year 1958., The circuit uses germanium...