optics replacement question (trackball)

tron guy

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I am still struggling with my wacko. I simply cannot put my finger on the problem yet.

It's not the wiring because everytime I put the up/down connector in the left right optic board it works.

I got an extra set of boards that worked for awhile, quit working, I whacked the control panel and it worked again,(for hours) now it's not again.

I want to change the optics on the pcb's, and I do have extras.

my question is: are there different values of optics?
the originals and the ones I have for replacement are different, though I could make the new ones "fit into place"

the numbers on the current stock optics are:
MOC7811
B252

the new optics have numbers:
H22A1
007

as I stated before they have a different frame to them, but they can effectively be the same. hard to explain without pics I know.
do the numbers I listed above matter?
 
try reflowing the solder on the header pins. They're notorious for cracking due to being plugged and unplugged often.
 
yeah I did that, and...... changed the optics. no help

maybe I need to put the old optics back in and test again.

problem is......I think a little circular trace was lifted when I removed the solder in the first place, from one of the legs of the original optics.

not sure what to do about that.
 
problem is......I think a little circular trace was lifted when I removed the solder in the first place, from one of the legs of the original optics.

not sure what to do about that.

find the next accessible area that trace leads to and jumper it to there. You mentioned that it was not working then you hit it and it began to work. This tells me there is a physical problem like wiring or a bad solder joint or bad trace. Possibly a pin at a molex connector not making good contact.
 
find the next accessible area that trace leads to and jumper it to there. You mentioned that it was not working then you hit it and it began to work. This tells me there is a physical problem like wiring or a bad solder joint or bad trace. Possibly a pin at a molex connector not making good contact.


I need to look again. It didn't look like the trace led anywhere.

funny thing is....I had my original trackball board in there, worked, then didn't work after rebuild.

put alternate board in there, worked, didn't work, smacked the control panel, it worked for awhile, then didn't (upon new power up after game was off) ahsn't worked since going back and forth between the 2 boards.

I am sure it is possible that both boards have connection issues, they are old.
 
might not even be the optic board. My tron spinner had issues for over a year. I couldn't figure out what could be wrong. Thought I had checked everything. Turned out one of the pins in the molex connector at the PS board was not making good contact. When I was testing the voltages at this connector I shoved my meter lead in there with the pin and basically bent it enough where it was making good contact. It was more or less a mistake but it solved the issue. Works great now.
 
might not even be the optic board. My tron spinner had issues for over a year. I couldn't figure out what could be wrong. Thought I had checked everything. Turned out one of the pins in the molex connector at the PS board was not making good contact. When I was testing the voltages at this connector I shoved my meter lead in there with the pin and basically bent it enough where it was making good contact. It was more or less a mistake but it solved the issue. Works great now.


I keep thinking it's obvious and easy like wiring or something.
but each time I take the connector and move it to the other pcb it is flawless, and if I move the working connector to the one with issues, it doesn't work.
very odd
 
UPDATE:
so I have located the proper optic replacement parts, but it did not change. these boards still do not work.
Bob Roberts looked at this picture and says "I doubt any of those parts are bad" so I am wondering what some of you guys may think could be the cause of this board not working.
I have reflowed solder to the pin connectors, changed the optics, and reflowed solder ina few spots that may have been suspect.

Do I change the ram chips (or whatever they are) first? the capacitors? test every single diode/resistor on there?


I suppose it's worth mentioning that I have 2 working boards and my game is 100% operational at this point.
I want to solve this mystery though and offer these up to someone who could use them.
 

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Looks like the same setup that tron used. Although the board is layed out differently it has the same components. Tron used an OPB822S optic which is basically two switches in one housing. Yours has two separate optic switches but I can almost bet the OPB822S will drop right in and work. Do a search on tron spinner and you will find tons of threads on the subject. You will find in most cases its either the LS491 or the optic switch.
 
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there is an ls339 on here and the optics used are MOC7811 's

since I changed the optics I suppose that ram chip (or whatever it is) is next. may as well change the caps too huh?
 
Its a counter.. If you look at the schematic for the optic board, you should see that there is basically an clock pulse and a direction toggle..you can try observing with a scope/meter and or toggling with jumpers to see what part of the circuit is working..You can also look at the output of the counter there should be an 8 bit word that should count in binary as the optics trip.

Andrew
 
Its a counter.. If you look at the schematic for the optic board, you should see that there is basically an clock pulse and a direction toggle..you can try observing with a scope/meter and or toggling with jumpers to see what part of the circuit is working..You can also look at the output of the counter there should be an 8 bit word that should count in binary as the optics trip.

Andrew


that would fall outside the realm of my experience/capabilities. :)
 
Yes its a counter and its a rare IC. I just got 400 of them in stock yesterday and let me tell you it wasnt cheap by any means. I was lucky to even find them.
 
Yes its a counter and its a rare IC. I just got 400 of them in stock yesterday and let me tell you it wasnt cheap by any means. I was lucky to even find them.
you are talking about the bigger of the 2 chips on that board huh?
how much are the if I want to replace them?
 
Yes the 74LS491, I am selling them for $7.50 each. Mark at arcadechips.com has them for $8 each. I think arcadecomponents has them too. Thats about it, probably wont find them anywhere else.
 
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