U-Trak jitter

[jeffremiller]

Anyone have experience with the Ultimarc U-trak trackball?

I just received mine and plugged it into usb (ordered the usb interface too)

It is working, sort of... but very jittery... especially on the horizontal axis.

Any thoughts?

[Turnarcades]

Check there is no dust inside, check your USB drivers and give the ball chance to settle in. Just give it a damn good spinning for the first few days in every direction and it should feel smoother.

[solowCX]

Mine definitely has this issue. What I found by taking it apart is that it seems like the rollers that the ball moves do not fit perfectly, causing them to move left and right sometimes. I am still working on my cab, so I don't know if it will hold up, but one thing I did that helped was to push the circular metal end pieces as close to the roller as possible and then tape them down. Not exactly the most ideal solution, but in the early tests I did it seemed to help a little.

The other problem I have is that sometimes I can get the ball to jump up off the rollers if it is a somewhat fast or sudden roll, not sure what to do about that though...

Overall it seems like a pretty good trackball, but I was expecting something a little smoother when I got it. It could just be I got a unit that was less than ideal.

[Turnarcades]

Andy, any thoughts on this?

[jeffremiller]

Well after a bunch of tinkering... I  have it isolated to the horizontal axis.

Even a huge spin on the ball only moves the pointer a little on the horizontal.

Working with Andy via email to resolve.

Thanks everyone.

[Ummon]

I had some slight worries about something like this when it came out because of its height relative to where the rollers would have to contact.

[AndyWarne]

I had some slight worries about something like this when it came out because of its height relative to where the rollers would have to contact.

This height is exactly the same as the Happ trackball. The contact points on the ball are the same. This was one of my design requirements. This effect is no greater on the U-Trak than any other trackball, when spun to the limit.

The problem sounds like a faulty optical encoder PCB. This could be confirmed by swapping the 2 PCBs over.  A replacement is on the way anyway.
Andy

[Ummon]

Ahh, thank you. A mistake I made by eye-balling it.