G07 Repair Story

QuartrArcade

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Figured I'd post this one as it was a little more challenging than most I see. I have a big box of chassis from various games and deals over the years. Pulled out a clean G07 chassis that was recapped with a new flyback. Hoping it was just pulled working and set aside I test it and get nothing at all. Check the B+ and it is at 150 VDC. Pull out the flowchart and it says to pull X701 (x-ray protection transistor) and recheck. Still no picture, start checking the 900 series components and look for a bad solder joint or connection, but no luck at first. Finally see that one of the joints on the flyback was never soldered by whoever rebuilt this.

Figured that would solve the problem, but still no picture and high B+. Double check the 900 components, but no luck. Finally start again by pulling X701 per the flow chart and the picture comes up. Figure it has to be a 900 component, but no luck. Finally occurred to me that maybe X701 was the problem and sure enough it was bad. Replaced X701 and the monitor came up but colors were missing.

Give a firm push on the neck board and colors come back. Check the neckboard socket and every pin solder joint is cracked. Reflow the solder joints and it came back to life completely.

Not sure what the moral is here, I hate giving up on repairs like this and it felt good to bring it back. Of course my time was probably better spent just rebuilding one of the other chassis in my pile, but still a good feeling.

Hopefully this will help somebody down the road.

Anthony
 
depending on who you talk to when the old flybacks blow up on these, they'll tell you the HOT is still good. considering I've thrown caps and flybacks and a ton of fresh solder at these things and have never gotten one to work, nor have I been able to get what I consider an accurate test of the HOT, I'm gonna have to say the HOTs are blown.

I also replace the pigtail fuses with fuse holders I creatively mount to the left heatsink.

any other advice?
 
I have only seen cracked solder joints on one socket before. Odd thing is that virtually every G07 I have worked on (with old caps) had at least one of the legs of the 10uf 250V cap on the neckboard floating completely free....
 
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