The original application of this 1967 Ferranti circuit can be changed so that it functions as a pass sensor shield for gears and other moving objects.
The TSC102 integrated circuit from ST-Microelectronics consists of a current sensor system that, in...
This circuit was found in old documentation, but the transistor may be the modern equivalent BC547....
The IC used in this project is not common these days, but if you have one you can build a high...