Free circuit schematics - wiparat.com

This is an example that demonstration how to control some devices via USB interface. The PC software program with delphi. Feature:
- CPU PIC18F4550 with full speed USB interface at 48MHz.
- USB 2.0 compliance - Use on-chip USB driver
- Control 1 stepping motor.
- MPLAB C18 for firmware at USB devices side.
- Delphi 6 for PC [...]

This circuit will allow you to control the speed of an AC motor, for example an electric drill. The way that this circuit works is as follows. The bridge rectifier produces dc voltage from the 120vac line. A portion on this current passes through the 10K ohm pot. The circuit comprised of the 10k pot, [...]

I got this from a dosing pump control circuit.
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