Tech: G07 - right hallf of screen missing (?)

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Tech: G07(Galaga) - Right half of screen missing (?)

*NOT FIXED *

My Galaga was playing great for the longest time and I decided to move it. Ugh. Now I can only see the left half of the screen and a line right down the middle. It has been capped recently.

I know I've read about this somewhere but I can't find it. My boys b-day party is this weekend; please help!
 
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You have a partial vertical collapse, look at the vertical section of the chassis for cold solder joints and or hairline cracks
 
Okay, after reading about vertical collapse I should check out X401 & X402, around the 400s, right?

Thanks, I'll go check, darnit.
 
Double check that all caps are correct according to polarity.
 
Besides the transistors, look at those big resistors back there for cold solder, too...
 
You may want to re-read the original post
Okay, sorry, I was mistaken as I had not done a cap kit on this monitor. So I just did ... except I didn't have a new C407 so I tried a used, unknown condition 4.7uf 63v. The only caps I didn't have on hand were: C303, C302, C518, & C521. I also buzzed X401 (B-0.56, E-1.85) and X402 (B-0.56, E-0.95) and received the noted numbers (using the middle leg as ground, right?). I also buzzed out FR401 and it beeped continuity and a 0.04 reading either way.

So I put it back in and it was perfect! ... then I watched in horror as the 'right' side collapsed again. Ugh.

Then I remembered I had a G07 that I capped and flybacked but I hadn't tested so I threw it in. It was perfect! What a relief! ... but it was slightly off to the left and needed minor adjustment so I went to adjust the V.Height. Huh? The screen disappeared and all that was left was a small green 'cloud' about the size of a quarter upper-middle of the screen.

Double Ugh.

Any suggestions/advice for a newb?
 
most likely if you touched something and suddenly something doest work...check solder joints
 
I finished the cap kit last night but it didn't fix the collapse so, today, I swapped out known-good FR401 and C407 and reflowed the vertical section of the chassis for cold solder joints and or hairline cracks.

Bingo! I'm back to having a full screen of alien bugs!

Thanks all!
 
Sounds like you haven't found the problem at all, and the physical action of taking it out has made the cracked solder touch until it heats up and then voila, back to bad. Start resoldering and looking at everything. in that section.
 
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