25" K7000 flyback pad have a purpose?

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I was curious if the pad that is seemingly unused on a K7000 flyback is actually needed for anything.

It fell off very easily when I went to remove and install a new flyback, and now that I'm having issues with it, I want to rule out this first. It has no trace connecting to anything on the board, and surrounding it is just circuit board, rather than any kind of ground/voltage plane. Nothing on the top side either.

Probably seems silly, but doesn't hurt to make sure before I dig any deeper.

See my other threads for this on-going nightmare, but this time the "new tech" told me how the little microscopic lines printed in the circuit board (just texturing on the plastic) are infact traces and that pad needs to be there. I laughed at first but he kept pushing it on me even after I told him how literally everything else on the chassis has a giant trace to it and that this would easily burn up any "microscopic" traces. I'm definitely not doubting myself, and me asking here is certainly unrelated to that and just making sure there's nothing else (semi-reasonable) I am missing. Oy vey!
 
As for the chassis, it looked like at times it would give a very very blurry picture, but wouldn't respond to focus control, and then it seems like it would crackle or something of that sort after a minute or so then just go to a white or purple screen. Chassis seemed to work previously but definitely needed caps and a flyback.

I have reflowed the neckboard and as stated this has brand new caps and a brand new flyback. I believe the first time I turned it on I saw something that looked like a speckle of dust or lint sitting on top of the flyback kind of get "sucked in" towards the new flyback... not sure if that means it's bad? This is my first flyback and know they come bad from the factory enough to where it could be possible.
 
these are single sided. they're not multilayered boards. if there's no trace, it goes nowhere.

while the K7000 is often referred to as one of the easier monitor chassis to start doing work on, there are a great many things that get overlooked. the CRT ground for instance doesn't plug into the neckboard; ordinarily you have to splice it back together with the other half of the wire attached to the ground on the tube. if you skipped this step then the chassis can arc wherever it so chooses.

there's a number of resistors running from about the top-center (by the fuse) all the way to the voltage regulator (IC4) that over time if the chassis hasn't been serviced in 20+ years that will get so hot that they burn up or break solder pads/traces. how the chassis operates will vary in this condition: it will either not power up at all, or it will probably look really shitty. and installing new caps exacerbates these problems, cause the new fresh caps will be an even bigger draw on these weak points. you will need to reflow solder and if you notice any suspect pads then you will be scraping traces open and jumpering them with those cap legs you cut off.

R101 is probably the most suspect resistor. if you have a P538 chassis with a C36/69 configuration (2 separate poly caps) it's best that you replace C69, and also C38.

I personally replace the signal headers on these with open headers without friction locks so I don't have to fight to unplug them later. the yoke pins will need to be reflowed. I also molex the CRT ground; cause that's how Williams did it. ;)
 
We tested this in a cab here at our little collector "clubhouse" here in NJ that I share with several other KLOVers and two of the guys rent the place and even with their long lasting experience cpmbined we were all kind of like "What?" and they saw exactly why I had so much trouble describing it, lol, and said it themselves.

The game board used to test was a Street Fighter board which has a lot of bright flashes in the attract mode so we could see that it was getting some kind of signal but it's just a blurry mess with most of the controls doing absolutely nothing. Focus makes it a little darker if you go from one end of the knob to the other so to speak.

It worked fine (a little washed out, but it was on original caps + flyback) before, so I'm guessing maybe the flyback was bad from the factory? It's such a weird issue.

Oh well. My customer had a broken game shoved in the back of the rest of his "broken/I don't have room in the store for this" queue that had the same monitor chassis which worked so I'm going to throw new caps on that and call it good, and eventually I'll tend to this chassis again if he ever wants that other game out there since I've becoming his regular repairman.

Flyback looks good, but are we still on the "replace flyback regardless" basis for the K7000?
 
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did you happen to like... check the focus wire? you didn't reverse the focus and G2 wires did you? the fatter gauge wire is the focus, thinner is G2.
 
did you happen to like... check the focus wire? you didn't reverse the focus and G2 wires did you? the fatter gauge wire is the focus, thinner is G2.

I followed it exactly as it was on the old flyback.
 
some people go based off wire colors. on a K7000 they're traditionally both red, but with all the junk replacements out there who knows. just like the pots on the flyback, the wires even come out the same way, focus out the top and G2 out the bottom.

you said you have a blurry mess, implying no focus, and when moving the focus knob, the brightness changes.

this is a K7000. it's not a Nanao 2931.
 
some people go based off wire colors. on a K7000 they're traditionally both red, but with all the junk replacements out there who knows. just like the pots on the flyback, the wires even come out the same way, focus out the top and G2 out the bottom.

It should also be possible to use a multimeter to check which is which: set DMM to maximum resistance setting; connect one lead to pin 7 and the other lead to one of the wires; turn the screen pot. If reading changes that's the screen wire. I haven't tried with a K7000 flyback but with many other flybacks it works.
 
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