Scrap A Hard Drive, Build A Rotary Encoder. 26 Comments . by: Dan Maloney. January 7, 2018. Title: Copy. Short Link: ... Hooked to an Arduino, the motor made a workable encoder, ...

Mine is a Hobbypower 30A encoder, bought from ebay 2 weeks ago for $10 with a free motor. Yours looks like a slightly different revision of the same design (the sense resistors, middle right, are ...