ok, I EFFED up a guy's centipede, need some help

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I went to try to change a monitor on a guys non working centipede.
He happened to have a working centipede there as well, so that was cool so I
could trouble shoot a bit.

Anyway, as I am testing the non working one in different ways with the working one I got into a situation where the working one, started showing just a white or yellow screen.
It played blind, but no video recognition.

It happened shortly after I discharged the monitor in question(working game) not sure if it's relevant.
I had an extra monitor and hooked up the video wires and power to it, and got the same yellow screen.
Then I got the non-working centipede (which was playing blind) hooked up to the extra monitor i brought and it came up just fine.

So now I have a non working centipede that plays blind and cannot figure out the issue with the monitor. I thought maybe it was a sync issue.
I am hoping someone knows what I should do next.
The guy lives 1 1/2 hours away and I need to go back there next week and figure this out.
 
They both have original g07 monitors in them. The one I brought home with me, has a blown fuse, so that's at least part of hte problem with that particular monitor.(non working game, not working one)

It was also a bitch that I wasn't aware that these are basically horizontal monitors that are turned sideways into the cab, lol.
I took a vertical monitor and it didn't fit. whoops.

Another funny thing about it was teh working centipede had the 6 wires going to the chassis from the harness and it worked fine.

The non working one had the 6 wires and then a jumper from the purple wire(on the original 6 wires from the harness) to 2 points for sync.

The non working centipede came up fine on my k4900 with just the 6 wires from the harness.

I guess I would also like to buy a working centipede board to take back withme to have some additional trouble shooting for his 2 games.
so if someone has a 100% working one to sell me I would appreciate it.
 
The more you type, the more confused i get.

On good centipede, having everthing hooked up, move the video harness around (i few gentle tugs). If screen flickers, change colors it could be sync issue in the harness.

No offense, but wtf made you mess with his good machine? If the mintor you brought to the dead one you know was good, you troubleshoot the the dead game from that point. As you stated, you just made yourself responsable for the good machine now.

Kevin
 
yeah, I should not have messed with the good one, but I wanted to test everything out on the machine before I just "changed the monitor."

To clear it up a bit. I tested his pcb, monitor, power board in the working machine to trouble shoot.

Bottom line I suppose is....
A game is playing blind and I have a white screen.
The voltages on the power board test good.

The wiring is hooked up the the chassis correctly.
When I run the wiring to another working monitor I get the same
white screen.
 
Did you re-connect everything the way it was before you fiddled with it? If everything is connected properly I would check to see if anything came loose or isn't making good contact.

I was also wondering, why did you discharge the good working monitor?

I feel for you and would hate to be in your position. I appreciate you sharing this as it is a valuable lesson for everyone just starting out to learn.
 
i am still a little confused. Are his g07's working ? is it just his motherboard that you messed up ?

I think you said it worked ok with your monitor but not his, but then you said you needed a motherboard.
 
Machine #1 - Plays blind, dead monitor, blown fuse on chassis.
Machine #2 - WAS fully working.

Both machines have G07's.....the monitor in machine #1 was dead.
Plus one monitor he brought with him for testing or replacement. (wrong mount though)

Discharged monitor on machine #2 to test the dead monitor from machine #1 on fully working machine #2. After discharging the monitor, machine #2 now has no proper video output on the original working G07 .... nor does it work with the monitor he brought with him. (plays, but no video) Tested machine #1 with his monitor he brought with him and it came up fine, the once fully working machine #2 did not.

So he went from one machine needing the monitor repaired to now BOTH machines are down. Machine #1 needs a monitor, machine #2 he doesn't know what happened.

No confusion. :)

Was the video cable connected when you discharged ?
Have you tried swapping boardsets from machine #1 into machine #2 ?
 
Machine #1 - Plays blind, dead monitor, blown fuse on chassis.
Machine #2 - WAS fully working.

Both machines have G07's.....the monitor in machine #1 was dead.
Plus one monitor he brought with him for testing or replacement. (wrong mount though)

Discharged monitor on machine #2 to test the dead monitor from machine #1 on fully working machine #2. After discharging the monitor, machine #2 now has no proper video output on the original working G07 .... nor does it work with the monitor he brought with him. (plays, but no video) Tested machine #1 with his monitor he brought with him and it came up fine, the once fully working machine #2 did not.

So he went from one machine needing the monitor repaired to now BOTH machines are down. Machine #1 needs a monitor, machine #2 he doesn't know what happened.

No confusion. :)

Was the video cable connected when you discharged ?
Have you tried swapping boardsets from machine #1 into machine #2 ?

that's exactly correct, and the only thing I didn't do was put the working boardset into the other set up with my working monitor because it was so late, and I had a 1 1/2 drive home at 11:30 last night.
I don't mind that I messed it up. I know the guy and he's cool about it.
I think I want to buy an extra board as well when I go back to try to get 2 working boards.
Someone said before it sounds like a harness issue, and I agree. though I am not the expert.
 
I think I follow now... I think, lol.

If test monitor was G07, just swap mounts.

#2 monitor was tested in #1 and did not work.
Test monitor did work on #1
Test Monitor did NOT work on #2
Correct, just want to make sure :)

Obvious the Chassis on #2 needs to be repaired.
Test the #2PCB in #1.
If good, Put PCB's back in there own cabs.
Verify #1 is still working

#2 now has good monitor (test) and good PCB
Trace the video wires and see if they are making good connections and no breaks/cuts/slashes.
Worse case, I would buy some edge connector pins from Mike's Arcade and just replace the video wires with new ones. You know they are not worn and wires are not broken.

IF #2 now has good monitor (test) but bad PCB. You are in deep, deep dookie :(


Kevin



Machine #1 - Plays blind, dead monitor, blown fuse on chassis.
Machine #2 - WAS fully working.

Both machines have G07's.....the monitor in machine #1 was dead.
Plus one monitor he brought with him for testing or replacement. (wrong mount though)

Discharged monitor on machine #2 to test the dead monitor from machine #1 on fully working machine #2. After discharging the monitor, machine #2 now has no proper video output on the original working G07 .... nor does it work with the monitor he brought with him. (plays, but no video) Tested machine #1 with his monitor he brought with him and it came up fine, the once fully working machine #2 did not.

So he went from one machine needing the monitor repaired to now BOTH machines are down. Machine #1 needs a monitor, machine #2 he doesn't know what happened.

No confusion. :)

Was the video cable connected when you discharged ?
Have you tried swapping boardsets from machine #1 into machine #2 ?
 
Someone said before it sounds like a harness issue, and I agree. though I am not the expert.

Absolutely.... double check every connector, every pin, etc.
I've seen people hook monitors up just one pin off repeatedly and think it's a board issue. (not to say that's what you did or anything)

My only concern was the discharging scenario..... the voltage is looking for a path of least resistance to ground, have seen discharges take the path of the video input cables. Which is why I always disconnect the game pcb from the monitor before ever discharging and asked if you had or not. Doesn't take much to take out a chip or two.

The fact that machine #2 still plays, but has improper video is concerning of the pcb itself if everything is indeed connected properly.

Oh, and for future reference, you don't need to discharge if all you are doing is moving the power and video cable from one monitor to the other for testing like that. (i.e a second monitor sitting on a stool or something next to the machine)
Or even to swap out the whole monitor.
Only if removing the chassis from the frame which requires removing the anode from the tube.
 
Question: Why did you discharge the working monitor on the working Centipede? I don't see any reason why you'd have needed to do that?
 
Let this be a lesson to not test other peoples boards in your otherwise working machine. I used to use my qbert to test peoples boards. After taking out my power supply several times and the main pcb a couple times I finally broke down and built a test rig. The only reason I put it off was the fact that the qbert test rig is so involved but its saved my harware from getting toasted when dealing with unknown boards.
 
fyi.. bob roberts sells monitor extension cables for just such a thing... so you can test another monitor w/o taking it out of another game...
 
fyi.. bob roberts sells monitor extension cables for just such a thing... so you can test another monitor w/o taking it out of another game...

Yes, but you don't need it for a Centipede as the cables are long enough to set up a monitor behind the game without any problems.

Dylan, let me start with... Wow!

There is no valid reason for discharging a monitor before pulling it out of the cab for a monitor swap.

Centipede uses positive sync, so it will only have one 6 wire connector and anything else will be something that someone has hacked into place.

Machine #1, which fuse is blown? F901 or F902?
Machine #2, Does it play blind now?
 
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