This interesting circuit, from a digital documentation two years 1978 shows how to implement a circuit that measures the position or angle of a stepper motor controlled by a microcontroller.
This circuit was found in a 1980s documentation. The IC is the 7400 and should be powered with 5...
The function generator XR2206 is not very easy to obtain, but if you get one you can assemble this...
This circuit converts a 12 V continuous voltage from a battery into an alternating voltage of 110...