W/g 7500

coinopjunkie

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Okay I took my chassie out and confirmed it is a k7500 through W/G's website. My issue I'm having is sometimes it is in focus and sometimes it's not. I'm not sure if it's the monitor or the game. When I start the game it is out of focus I adjust that on the flyback and it now looks good play the game and some screens (scenes) are in focus others or blurry restart the game cold or right away starts blurry again. Any idea ? I'm thinking cap kit, reflow and flyback. The flyback looks perfect and I really don't want to place an order for just one flyback but I just bought this game and want to play it. So experts let me have it do you think it is the flyback? I know I can try a cap kit and reflow to see and then order the fly but I'd like to do it in one shot if I can. I know this much after working on 30-40 monitors, working on monitors sucks.
 
Probably flyback, but you can check the neckboard to see if the focus wire is firmly in the socket, and make sure the focus pin on the tube isn't damaged...
 
Thanks

Okay so I had enough capacitors and some time last night so I changed what I had which was quite a few. When I reinstalled the chassis basically the same thing happened except it started doing the hula when I turned down the brightness on the fly? turned it back up and played with the remote board and got it to calm down this was on it booting up only? during game play I don't see the movement like the start up screen. So I noticed the four corners are the worse I can't focus them it's like a convergence problem so I went to the neck to look at the rings and found them still glued together but they slid to the bottom of the neck board so I pulled the neck board off and the rings just slide off with barely touching them, looking at them they are suppose to be pressure fit (no screw) one of the tabs broke off and the monitor neck gets so hot it melted the hot glue so this thing would slide and move during game play. I'm thinking this is the major problem but no matter where I put the rings it doesn't get better or worse for that matter? Any ideas there? I'm still thinking that fly needs to be changed, But I also know these rings need to be dealt with two. Anyway I thought this was an odd one cause I have never seen a tube act like this and the rings moving during game play makes since but what dosen't is when I move (left to right or up and down) nothing seems to change.
 
are the rings all glued together or does each ring spin freely? more importantly, can you tell where all the rings lined up originally?

the focus issue is most likely the flyback. seems to happen on all of these. I suppose drifting focus or brightness is a lot better than a white knob K7000 flyback going bad right?

the clip you need for the neck can be found off an old 25" TV I guess. you'll need one that has the adjustable tightening bolt (which naturally you do not want to tighten too much) and that should at least prevent the rings from moving around. after that, I would silicone them all back together if you can get them back where they belong.
 
Thanks for the info

are the rings all glued together or does each ring spin freely? more importantly, can you tell where all the rings lined up originally?

the focus issue is most likely the flyback. seems to happen on all of these. I suppose drifting focus or brightness is a lot better than a white knob K7000 flyback going bad right?

the clip you need for the neck can be found off an old 25" TV I guess. you'll need one that has the adjustable tightening bolt (which naturally you do not want to tighten too much) and that should at least prevent the rings from moving around. after that, I would silicone them all back together if you can get them back where they belong.

the rings are all still glued together but no idea where they were on the neck I have a guess but with the melted glue smeared everywhere it is hard to say.

I will have to order a new one I guess, wife is going to kill me with all the money I've spent on these lately.

I failed to mention this is a 27" is it the same rings off a 25"?
 
I'm 100% sure it's the flyback. Just fixed this exact same monitor on a Blitz game. Monitor worked fine, but after 10-15 minutes it would slowly get blurry.. Put a new fly in, plus capped it and hit all the solder joints.. Monitor has been trouble free and running every day for a few months..

Make sure to go over the neck board.. As the trannies get hot and desolder themselves.. Same with the (3) large resistors.

Replace the fly.
Replace the fly.
Replace the fly.
 
Thanks for the info

I'm not so sure I stayed up till 230 in the morning working on it and I put a new set of rings on it and tried to get the convergence on and the convergence is still a little off but ran the thing all night and the focus stayed the same. I think it was the rings, when it was cold the rings were tight and glued down, when it was turned on for a few minutes the rings would float around on the neck causing the convergence to get off and appear blurry. The monitor does still jitter just a tiny tiny bit? Has some pin cushion but this monitor does have the pin cushion board but trying to adjust it with one set of eyes I couldn't see any change as I was doing it. And the convergence is different on the top and the bottom. I admittedly know nothing about convergence so that might be normal I don't know? I also did order the fly already but not sure I need it.
 
Cool on the rings, never had bad or loose ones.. But I guess that could be an issue. You do need a new fly, as these were kinda shitty from day one.. So it's the right move. Also, touch up every solder joint on the neck and chassis.. Cap kit is also a good move.
 
for as shitty quality as they are, I've never observed any major catastrophic scenarios involving bad solder joints on any of the U2000/U5000/K7400/K7500 chassis. about the only place that I've had to do any work like that though was on the neckboard at each of the color drive transistors. you have to resort to varying degrees of creativity with those, depending on if your traces are trashed or if it's just lifting solder pads. the lifting solder pads are easy enough to deal with, I just desolder the transistors completely out, scrape all the flux off with a dental pick, then reinstall them and just bend the legs at 90 degree angles through the solder holes (alternate the leg bends, go down, then up, then down again) and that should hold them tight to eliminate the solder pads from lifting anymore.

if the traces are damaged, then you have to resort to jumper wire hacks... do those however you see fit.

the flybacks are definitely all shit. K7500s in particular I've found to have the drifting focus/brightness. another facet you also have to consider is that the tubes in this generation were absolute garbage as well. weak tubes will also generate focus issues. you need to secure your convergence rings with a new clip first off, they're not supposed to move around like that. you can often times find their original position based on the discoloration on the neck from the parts that were exposed vs. the parts that were covered by the rings. then you can match it up with the glue lines.

I think I covered everything. lol
 
Cool thanks again

I did change the rings completely I used a set off of a 19" monitor are they the same? Anybody know? The old ones were falling apart. The monitor is now looking pretty good but I keep having strange sync problems. The game plays fine the picture looks decent it doesn't change anymore since the new rings it still needs to have the convergence adjusted better but once in awhile when I turn it on it's out of sync then I have to unplug the sync wires and replug them, I thought maybe a bad solder joint or similar but besides the fact I reflowed them already it doesn't matter if I unplug it at the board are through the harness it fixes it?
 
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