go7 playing blind all of a sudden

tron guy

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I was doing some soldering last night, and obviously the smells are pretty strong.

I thought I smelled something burning but figured it was just the solder, etc.

Well I turn around and my tapper screen is off. I coin her up and she plays. no pic

I kind of smell something burnt inside, and it appears that the monitor is not getting power.

Anyway, I have another chassis to throw in there tonite, but I did get a rebuild kit with flyback from bob roberts.

Should I cap it and change the flyback automatically? Even if I determine the fly isn't bad?
I mean it's a given that it will go bad right?
 
It's a G07 and it just died and it smells bad - very common in these monitors. The flyback is dead, the small fuse is blown, and the HOT is probably toast too. Might as well cap it while you're in there.

BTW: Be careful when you remove the chassis. The B+ filter cap probably still has a charge. Short the terminals out with a screwdriver to discharge it so you don't zap yourself.

-Ian
 
It's a G07 and it just died and it smells bad - very common in these monitors. The flyback is dead, the small fuse is blown, and the HOT is probably toast too. Might as well cap it while you're in there.

BTW: Be careful when you remove the chassis. The B+ filter cap probably still has a charge. Short the terminals out with a screwdriver to discharge it so you don't zap yourself.

-Ian

that's the big ass cap right? I have heard that before, and always do the discharge, though I have yet to hear or see a spark/noise.
thanks


I don't think I have a "hot" (unless bob puts itin the cap kit) guess I will do everything else and see if she works afterwards.
 
Yeah, it's the big cap. You won't have seen it spark unless you've blown a flyback before. Here's what happens: That cap is the filter in the B+ supply, and immediately after the cap is a fuse. Following that is the deflection circuitry that's powered by the supply. Under normal circumstances, when you remove power, the load on the B+ supply drains the residual charge out of the cap. But when the flyback fails, it blows the HOT and draws too much current, blowing the fuse, opening the B+ circuit. Then, when power is removed, the cap can't discharge because the fluse is blown.

The cap won't kill you, but do be mindful not to put your fingers on the terminals under the board while removing the chassis. Once you've got it out, short the terminals with a screwdriver. Should get some sparks unless it's been unplugged long enough to naturally dissipate.

You probably have a HOT. It's the metal bottle-cap shaped device with two mounting ears and two pins sticking out of it. It's included in the flyback rebuild kits because when the flyback goes, it almost always blows that transistor too.

-Ian
 
tell you what. It was more like an explosion when I discharged the big cap.
WOW

my screwdriver has some heavy burn marks on it, lol.

Anyway, I apparently ordered just a flyback with capkit and did not get a hot or anything I may need.

Should I just go back to bob and order a full rebuild kit? if he offers it that is

oh and I put a different chassis in there and the game works again.
 
When I rebuild a G07 that I am keeping this is what I have been ordering from Bob and replace:

(1) G07 Deluxe Repair Kit
(1) 680uf200v B+ filter
(1) G07 Replacement Pot Kit (4)
(1) GO7 R908 47K ohms 1/2 watt 4 pk (then you have 3 left for other repairs)
(2) 3.3uf50volt NP Radial Cap (these are the 2 caps not included in the cap kit. I figure they are right thee, I have it out, why the hell not replace them)
 
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