This powerful motor control was found in a Philips publication from 1970. The components are from that time and the circuit was designed for the 220/240 V power grid.
The frequency depends on the coil and is not found in the original documentation but should be...
This is a device for those who need to show that they know how to use digital electronics but have...
Using an operational amplifier with FET, this circuit from a 1977 publication can generate...