Help from the monitor gurus - G07 GO7

gobsgraham

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Not sure if it is Gzero7 or G capital O 7 but that doesn't really matter.

I screwed up and need some help. I had a G07 here that had the yoke wire connector broken into 4. The monitor came out of a Monte Carlo and I rebuilt the chassis and plugged it back in and forgot which yoke wires went where. I plugged them in based on how they were formed rather than coming here in the first place to check and see how they should be connected. When I plugged it in R515 smoked because I had plugged flipped the Red and Grey wires (the two wires on the right when looking at the chassis. When it was smoke there was vertical collapse. Now when I plug the wires in properly, the whole image is blue and shrunken to around 3 inches by 6 inches. I will add a picture tomorrow.

Did I just smoke R515 or do you think that I did other damage at the same time?

Do you think I would have damaged the yoke? or anything else?

Has anyone else done this before? I found one or two threads with similar cases and R515 but no real closure on how to fix things.

Hopefully someone else has done this and can guide me to the quickest way to fix it and regardless of what happens I will make sure that I update the thread and so the next newbie that does this can hopefully fix theirs.

Thanks
 
Here is a picture. I will measure the yoke when I get home today.

I am placing a Mouser order today so if anyone knows of other common parts that get fried when this happens I would appreciate it.

Thanks
 

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that being the case, you will have to look for what other parts you blew when you hooked it up wrong. sorry, can't be more specific as it is going to be a crap shoot
 
Thanks Dokert. I appreceiate the help.

If anyone else has done this and has a list of what blows that would be great. Otherwise I will just start pulling and checking everything in the circuit.
 
Theres a good chance that one or both of the vertical output transistors are bad and that the 68 ohm fusible resistor in the vertical section is also bad. I would guess that the horizontal section is robust enough to withstand this sort of thing for a few seconds and based on the fact that you still have high voltage it seems to be fine.

However unlikely I'd also look for blown traces.
 
Deleted last post because I am not sure my brain is turned on.

I have one good chassis left and am afraid to plug it into this tube. I am not sure what I am going to smoke or which way to plug in the yoke wires.
 
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Uggh! So the original chassis that I pulled out of this was marked in sharpie WBRG so that is how I have been hooking up the chassis' (although at some point I think I was also flipping the red and the grey). I don't believe that WBRG is an accurate flip as it is connecting the vertical to the horizontal and vice versa. I put the chassis back in the cabinet and connected it via the standard G07 (BWGR) yoke connection after confirming on my Ms. Pac monitor and it has a bright colorful picture now appears. I could have saved myself a ton of time and effort had I spent more time on here and Bob Roberts. I eventually clued in while reading Bob's flipping the yoke page (http://homearcade.org/BBBB/yoke.html). Neither the standard connections or the flipped connections matched what was written on the chassis.

I have a bit of drooping in the top left corner but other than that it looks pretty good. Apparently shutting it down quick enough was enough to keep from damaging anything serious.
 
Thanks Dokert. It was late and I was just happy it was running so I just adjusted it until I got it to sync and went to bed. I will fine tune it today.

Thanks again for everyone's help.
 
FUUUUUUUCCCCCCCKKKKKK! This monitor was brought back to me because it had Horizontal/vertical collapse from a Monte Carlo. I ended up putting a different rebuilt chassis on this. Everything worked fine here and I burned it in for 24 hours.

The guy brings it home and installs in and an hour later it has collapsed again. Although he said he turned it on the next day and it was fine for about an hour again.

60 games in 6 months and the one I give away for cost is the only one that is giving me any problems (recurring problems anyways).

Should I be changing my focus to the game. Could the big blue be causing this?

Thanks
 
Nope, not a Big blue issue. You have a monitor issue. You most likely have a hairline crack or cold solder joints on or around the vertical transistors.
 
So much for my burn in. I am going to get another one ready to go and flip it out for him again and see what happens. If it blows again I'm going to give him a CGA to VGA board and we can all move on with our lives.

Thanks Dokert.
 
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