is a high-power DC brush motor speed controller, typically used as the "heart" of household mini lathes like the CJ0618. It converts input into a variable 0-180VDC output to precisely regulate motor speed. The Story: "The Heart of the Iron-Worker"
The board features several internal potentiometers to fine-tune performance. These are usually pre-set but can be adjusted for specific needs: jymc220bi schematic full