Trackball diagnostics

[Wade]

Okay, I finally got back on my trackball project.  I hacked a new mouse and it seems to work properly.

I read on here before that bad optics are very, very uncommon.  But I have a problem that sure seems like a bad optic board.

If I attach the Y/G wires to the hack, my mouse moves back and forth properly.  If I connect the B/Br wires to the hack, the mouse moves only one direction, and not very smoothly or consistently.  If I connect the B/Br wires to the Y/G board, the mouse moves properly.  So it sure seems to be a bad board.

The board has 3 resistors, a little chip, and the two optic parts.  Should I try replacing the optic switches first?  Or just buy a new board?  The trackball is an imperial (don't know if the optic boards are are all the same or not.

Thanks,
Wade

[BobA]

If I attach the Y/G wires to the hack, my mouse moves back and forth properly.

When you say hack you do you mean a single axis on the mouse?

If I connect the B/Br wires to the hack, the mouse moves only one direction, and not very smoothly or consistently.

When you connect the B/Br wires to the hack do you mean the same connections as the  Y/G wires were connected to on the mouse?

If I connect the B/Br wires to the Y/G board, the mouse moves properly.

Leaving the B/Br wires connected to the hack at the same point the other ends were switched to the optic board that the Y/G wires were connected to.

So it sure seems to be a bad board.

If the answers are Yes to all three clarifications then it does sound like something amiss in the optic circuit that connected to the B/Br board.  

The boards are interchangeable did you try using the B/Br board in the Y/G position?

It could just be a bad solder joint on the connector or a broken trace as well.  Check for these before changing components.  Also blow out the slot on the optic sensor on the bad board maybe even use some alcohol to clean the slot.


The chip is a 74HC14 and could be replaced if you are good at pcboard repair.  Not sure of a source for the optics.  


Info the the circuit here
http://www.members.shaw.ca/bakaye/tballhack.htm

Good Luck

BobA

[Wade]

If I attach the Y/G wires to the hack, my mouse moves back and forth properly.

When you say hack you do you mean a single axis on the mouse?

Yes.  I knew that mouse axis worked so I wanted to eliminate any variables I could.

If I connect the B/Br wires to the hack, the mouse moves only one direction, and not very smoothly or consistently.

When you connect the B/Br wires to the hack do you mean the same connections as the  Y/G wires were connected to on the mouse?

Yes.

If I connect the B/Br wires to the Y/G board, the mouse moves properly.

Leaving the B/Br wires connected to the hack at the same point the other ends were switched to the optic board that the Y/G wires were connected to.

Exactly.

So it sure seems to be a bad board.

If the answers are Yes to all three clarifications then it does sound like something amiss in the optic circuit that connected to the B/Br board.  

The boards are interchangeable did you try using the B/Br board in the Y/G position?

Yeah, it sure seems like that board is bad.  Yes, I tried the B/Br board in the Y/G corner of the trackball (in case the wheel was misaligned or something) and it still didn't work.

It could just be a bad solder joint on the connector or a broken trace as well.  Check for these before changing components.  Also blow out the slot on the optic sensor on the bad board maybe even use some alcohol to clean the slot.

I looked it over but everything looked okay.  I'll clean the sensors, just in case.  They appeared to be clean.

The chip is a 74HC14 and could be replaced if you are good at pcboard repair.  Not sure of a source for the optics.  

Yeah.  I'll shop around and see what I can find.  Might be worth just buying a new optic board for $10 or so if I can find one.

Really regretting buying the used ebay trackball now... my cost is rapidly approaching that of a brand new trackball.

Wade

[hevnsnt]

Yeah, but now you have a lot better understanding how a trackball works don't ya!

[Wade]

Yeah... unfortunately.

Wade