The potentiometers get worn and dirty, and the varying resistance from the dirt and loose contacts causes the jitter. You can try cleaning them with electronics

The potentiometers get worn and dirty, and the varying resistance from the dirt and loose contacts causes the jitter. You can try cleaning them with electronics cleaner or alcohol, but it probably won't work for long, if at all. http://vintagegamingandmore.com/atari-paddle-repair/ http://vintagegamingandmore.com/atari-paddle-repair/ Commodore paddles are similar, but use 470k ohm linear pots. You can use 500k ohm ones if you can't find 470's, but you probably won't have a problem finding them.