So, I have a pair of [mismatched] turntables (Stanton STR-30 and STR-60) that I got to mess around with. They are both direct-drive and have seen some use. The STR-30 is ok...nothing to write home about. The STR-60 needed some work. The power cable receptacle was loose so the table would randomly lose power if you wiggled the cable. No problem...opened it up, re-soldered it and now that works fine and is sturdy.
Playing around with DVS (traktor Scratch) I notices that the pitch changes were way off. At "zero" it was ok. But nudging the pitch fader down (speed up) just a little (like 1mm) caused it to jump 5-6 bpm! Then I noticed that moving pitch fader up (slowing it down) actually caused it to speed up until it was at about the 2% indicator before slowing down to normal speed AND THEN start to slow down.
Ok... decided to try to calibrate the pitch slider...grab my mini screw driver and begin adjusting it from below while the platter is turning and watching the dots and noticed something weird...while my hand was touching the screw driver and it was touching the pitch adjustment pot, the pitch fader worked precisely as it should...as soon as my hand stopped touching the screw driver, the speed was all over the place...even just the lightest touch on my hand was enough to restore the pitch fader to working correctly...but as soon as my hand left it it as messed up. Tried touching it with a pencil and a cotton swab and neither worked. only my hand worked. As much as I want to believe that I am imbued with a magical touch, I am guessing a much more banal explanation like a grounding issue or something...I just can't figure out what it is though!