Replaced the rollers in my track ball and it's still acting up

action53

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Replaced the rollers in my track ball and it's still acting up

Up and down works great now, left and right sucks. Switch the wires on the boards and left and right works and up and down sucks. Switch it back and they both work. Up and down always works, left and right is intermittent.
 

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The resistor on both of the boards measure 100 ohms. Playing with the cable or wiggling the plug doesn't have any effect on the randomness of the left and right movement. I air dustered the thing that reads the wheel and the wheel isn't hitting the reader and it's not bent. It's in an upright centipede
 
Cold cracked solder joints are pretty common on the header pins for those opto pcb's. Reflow those and see if things improve.
 
Reflowed all the solder on the optic board and no change. I swapped the boards so left right always works and up down is intermittent so the game is somewhat playable. It slowly creeps the shooter up during game play. How good are those red replacement boards?
 
I've used the red optic boards for years with the 60 in 1 JAMMA boards, they work fine for that application. I honestly haven't run them in a dedicated Centipede, since I always had vintage spares when needed.
 
Have you considered that your problem might be the trakball circuitry on the logic board? :confused: (i.e. bad pullup, bad inverter, bad flipflop, bad counter etc)
Might also be bad connector/harness/edge-connector contacts etc.
 
somebody mentioned two ram chips that had to do with a buffer for the trackball on the pcb
 
Cold cracked solder joints are pretty common on the header pins for those opto pcb's. Reflow those and see if things improve.

I reflowed and it got worse, lol.

Have you considered that your problem might be the trakball circuitry on the logic board? :confused: (i.e. bad pullup, bad inverter, bad flipflop, bad counter etc)
Might also be bad connector/harness/edge-connector contacts etc.

I swapped the plugs to test that and the problem was definitely in the optic board. Anyone got a spare for sale or know where I can get one?


For the time being I swapped the bad board to the up/down and put the good one in the left/right so the game is half assed playable until I get a new optic board. I would much rather have an original green than an aftermarket red but I'd rather have it working than not though.
 
If it is definitely the opto board, then also inspect the copper traces. I seem to remember some reports of "hairline" cracks. You can also use ohm-meter to check conductivity between all the components.

Last option is to replace the opto.
 
I checkered continuity of all the traces and they checked out, the little resistor checked out too. I think it might be that black thing that reads the wheel. I'm just gonna order one one and be done with it. Between parts and shipping so far it probably would have been cheaper to just buy a whole new track ball but then I wouldn't have learned anything so I guess it's still worth it. Maybe Bob will send me a trinket this time, a buddy of mine gets moon pies and trinkets thrown into his packages all the time.
 
I recall when I bought my Centipede, I considered buying a rebuild kit for the trackball, but I saw that an entire new trackball assembly was only $20 more. Glad I took that route.
 
I checkered continuity of all the traces and they checked out, the little resistor checked out too. I think it might be that black thing that reads the wheel. I'm just gonna order one one and be done with it. Between parts and shipping so far it probably would have been cheaper to just buy a whole new track ball but then I wouldn't have learned anything so I guess it's still worth it. Maybe Bob will send me a trinket this time, a buddy of mine gets moon pies and trinkets thrown into his packages all the time.

my centipede was doing the same thing , and i was using 3 working trackballs.
i ended up getting the pcb repaired.

Also if you are using the wrong trackball boards it wont work either.
this is when you wanna just take the ol trackball out, and slam it on the ground
and swear for an hour.
 
my centipede was doing the same thing , and i was using 3 working trackballs.
i ended up getting the pcb repaired.

If I leave the boards in the ball and swap the wires the problem follows the board, not the wire. No matter what wire I plug into my bad board, it doesn't work. No matter what wire I plug into my good board, it always works.




Also if you are using the wrong trackball boards it wont work either.
this is when you wanna just take the ol trackball out, and slam it on the ground
and swear for an hour.

http://www.therealbobroberts.net/tboptic.html

The new Happ boards'll work, you just have to swap the wires.
 
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