4600 flashing or streaking

popcorn

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I'm not sure what to call this symptom, flashing or streaking, but I brought the monitor in dead, installed a cap kit and now I see it flashing and streaking. Despite what the phone camera shows, the picture is pretty good when it shows one and really bad when it doesn't. It does this on the bench and in the game.

I have worked on all the solder joints and cleaned all the pots. The Cap Kit came with a brightness pot for the interface board but this chassis didn't have that type of pot so I couldn't install it. Should I be concerned about the edge mounted pot as well?

After resoldering everything in sight I seem have it where while I didn't see anything even remotely obvious wrong, I haven't seen it do this brightness flash for a hour, but if I tap on the deflection board I can make the monitor jump a little so I'm not sure I have all the bugs out. I have poked around the deflection board with a plastic tool trying to locate what is loose and can't. I'm suspecting the edge connector but it "looks" as fine as any I have seen.

I'm looking for ideas...
 

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The 4600 is well known for many cold solder joints one the main board as well as on all the plug-in daughter cards (power regulator, video interface, and XY).

Be sure to examine closely the soldering of the header pins for the video interface board on the main board side and on the video interface board itself.
 
I have been all over this chassis for cold joints. I think I reflowed every one by now. It stopped flickering when I banged on it but when I ran this for a couple hours afterward, this symptom returned. It looks just like it does in the pics. Bright on one side and no visible raster any where else. I think its a loose junction internal to a component. I replaced the Horz driver with a sub recommended by Xanen (1138 If I recall correctly)
 
Oh yes, I have gone over every solder joint everywhere.

As for the brightness pot I said originally:

"The Cap Kit came with a brightness pot for the interface board but this chassis didn't have that type of pot so I couldn't install it. Should I be concerned about the edge mounted pot as well??

The cap kit had a flat mounted pot for use on the solder side of the board I believe, and this board did not so I couldnt use it.

I tested it as best I could, took it out, measured it while sweeping it through its range from both ends, cleaned it anyway, put it back in, still the same.
With all I have done, I would have expected something to change by now. For the worse or better!
 
You must have either a P317 or P318 version of the video interface card. I have not seen the vertically mounted black level pot going bad like the earlier version board did with their horizontally mounted black level control.

It's possible your picture tube may have internal problems.
 
It's possible your picture tube may have internal problems.

I have a sencore tube tester and I tested the tube originally as a matter of practice and it had a G1 Short after a rejuv on the red gun, but it was able to be cleared. I have not seen it since.

Would I be able to measure the effect of a shorted G1 on the neck board socket, if in fact you are correct and the G1 shorts only after a long period of being on?
 
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