Screen jitters, measuring B+ 25" K7000

As do mine, while trying to use the monitor crosshatch pattern to align and focus the screen the M2 tube with M1 chassis is going nuts but for the most part the rest of the game looks good
 
Dr. Willy, yes I saw a few shots that looked like my symptom.

Buffett, I have swapped chassis between the k7000's that I have and now I'm scratching my head a bit. I will describe below and M1 is the original monitor that was in my MK1 cab, M2 will be the untested monitor I picked up from 8bitnintendo for 50 bux. He's got a lot of 25" monitors so if anyone near Napa CA want or needs a project, hit him up.

M1: Issues were jail bars, dark screen, jitters and didnt always have a picture when turned on, wiggle of the neck board while pulling (neck board off direction) pressuer was applied would get it working. It recieved a full cap kit including filter cap, voltage regulator, HOT and Flyback. This brightened the colors and got rid of the jail bars. Aslo recieved a reflow in several recomended spots on chassis and neck board pins so now it fires up every time. Still jitter issues on any screen in game or diagnostic mode.

M2: Had a blown fuse, replaced it and it blew right away. Also had many pots rusted in place, they would not turn. Replaced all neckboard pots, 50/60 pot, horizontil pot, VR, HOT, flyback and ALL caps. Fired her up and had a pic. Needed adjusted, could adjust all but width so it might be a bad coil. Other issue was there was barely any red. There may have been jitters but honestly I don't remember. Will go back and try again tomorrow. Also this has had no reflow done.

So, swapped chassis. M1 tube with M2 chassis and jitters are a lot better as most screens do not have it in the game, most noticeable would be the Goro screen but it's steady until the white lettering pops up then it goes to shit. Also it still needs stretched out for the width. Also colors look good and I have red.

Now, M2 tube with M1 chassis. Have all colors but same exact jitters as the M1 tube/ chassis assembly.

I expected to be missing red on one of the combinations above but I don't so I'm suspecting the M2 chassis should be reflowed.

ok, now big question?

what is your B+ reading now on both chassis after they warm up.
do they stay at a solid 130vdc give or take a volt here and there, it will fluctuate a very little bit depending on what is on the screen.

or does the voltage dip in and out several volts as you change screens or it goes from black to wight and heavy color transitions flash quickly.

or does it dip way down if you turn up the contrast pot real high?

you will need to watch your meter as you play the game and turn the contrast pot to see what it does.

Peace
Buffett
 
As do mine, while trying to use the monitor crosshatch pattern to align and focus the screen the M2 tube with M1 chassis is going nuts but for the most part the rest of the game looks good

messed with mine some more and yes it jitters through all screens, diagnostics, crosshatch etc etc. I got my monitor dialed and starting playing it, once stuff on the screen is moving around and you are focused on the game you really don't notice it at all. At least I don't.
 
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