WG 4901 problems

Cmndr Brain

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I have a WG 4901 that mostly works. I got it from a guy who said it worked fine before he did a cap kit. I know this guy to be a good person and have no reason to doubt him. I have double checked the caps to be all the correct values and positioned correctly. I don't see any cracked/bad solder joints. Could it be a bad cap somewhere? Should I just to a new cap kit just to double check? The only problem seems to be on the left side, mostly in the upper corner where the 3 colors don't converge correctly.
 

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That's not a chassis issue. You should check to make sure the yoke isn't tilted to far towards or away from that corner, but you probably need some convergence strips to dial it in. Don't normally see it that far out of wack, but it's a deal with the tube/yoke/rings, not the chassis...
 
Aw crap... That's the part, I'll admit, I suck at. Any suggestions on where to get information on adjusting the yoke/rings?
 
He probably whacked the convergence rings out of place when removing/reinstalling the chassis. A previous line, mark, or glue residue might help you readjust them. Make sure all the rubber yoke wedges are installed too. Obviously it worked before he messed with it, so see if there is anything loose or out of place.

-Ian
 
Just to verify, I put in a spare chassis that I had and still had the same problem. So, in short, Modessitt seems to be correct. Retro, there was glue and it looks like all the convergence rings were still in alignment. Also, the there are 3 rubber wedges that are glued between the yoke and tube and doesn't seem like there was another. I don't know what he whacked but everything seems spot on. I know enough to do cap kits w/o killing myself, but some of this other stuff like yoke adjustments, I don't know what I can and cannot touch while the monitor is on. Looks like more research.
 
Yeah, you need some CRT alignment strips. Call Wells, they will still sell you some. Or Chad over at Arcadecup.com will sell you some. Heck, I bet even Modessitt will sell you some.
 
Well, well, well. I would like to thank you all for steering me in the right direction. After reading Modessitts sticky on convergence and watching the video Level42 added to that sticky, I found the courage to play with the existing convergence strips. After taking one off, figuring I couldn't screw it up anymore, I heard a "tink". "What the hell was that!" Well looky, looky, what I found between the tube and yoke (see image #1). Although it's still not perfect (see image #2), holy crap what a difference. It could probably use 1 more strip to correct the top, but other than that, it's now a usable monitor again.
 

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