I got some off of Ebay and just tried to play Super Breakout. It was quite a challenge as the little bar kept jerking and blinking all over the screen instead of moving smoothly side to side. Any suggestions?

http://www.zutco.com/atfaq.htm

How do I fix my jumpy paddle controllers?
Take the back off of your paddles and squirt a little WD-40 into the opening in the pot underneath where the wires are soldered on. Work them back and forth a few times and try that old Video Olympics cart.

Thanks one again, GC, that worked great! I went to that site and also found out that some 7800 games need the second button!? I had been using 2600 joysticks until now and was blissfully unaware of that.