Screen jitters, measuring B+ 25" K7000

HotBlue02

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Looking to make sure I measure this correctly. My manual says to check IC4 pin 4 on the main board and P202 pin 3 on the neck board. Does this mean I put on lead of the multimeter on each spot to get my reading? Or am I putting my black lead to ground and checking both spots for voltage?
 
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Ok, with bkack lead to ground I have 131.2 vDC on the blue wire closest to the fly back and 169.6 volts DC on the red wire. This monitor had recieved all new caps including the filter cap, VR and HOT. This took care of the dark colors and jail bars but the screen still has a bit of the jitters. Mostly not noticeable during gameplay but it's there and I want it gone. Not sure what is causing it so any help to resolve it would be great.
 
jitters how?

side to side or up and down or diagonal?

a video will help.

different fixes for different jitters.

i would also replace the flyback.

Peace
Buffett
 
Perhaps jitters is not the correct term for the issue. I tried to capture it on video but it's not picking it up. I can't find an example on YouTube to share so here goes my best description. It's almost as if you were to view something thru the surface of water like looking down into a pool
 
Yea that kinda describes it. It's very minimal. Enough so that my camera can't pic it up but its still annoying
 
ok, that sounds like bad caps and a flyback.

if they have not been done, they need to be changed in order to progress further.

both will cause your issues.

if you need parts i have them.
visit my shop below in my sig.
or you can visit my site and email me.

if you need it repaired, your welcome to send it in.

Peace
Buffett
 
All caps have been done along with HOT and VR, will try a flyback tomorrow
 
Not sure how to check that yet but I'm gunna have to learn.

Finally got time to slap in the new fly back and no change. So, I decided to rule out the pcb and plugged in a golden tee 2k board. Monitor looks great, a nice steady picture. Decide to yank the MK1 pcb from my MK2 cab thats on a 6 in 1 switcher and plug that in, the problem is back. . . WTF!!! I don't get it? Help

cool.

check the resisters in the VR circuit as well.

Peace
Buffett
 
your gonna have to try and catch it on video.

the only other way to see the issue if you cannot capture it on video is to send in the chassis for testing.

now if your running a MK1 and MK2 on that monitor, those games have a normal shake to them on some attract and level screens by default, it was in their programming, MKII was worse than MK I.

if all other games play with no problems, i am inclined to believe the MK PCB's are doing it.

Peace
Buffett
 
Hmm, well I see the shake, hula, jitters, wobble or whatever is going on thru out all screens for mk1 including Rom check, service menu, screen stuff in diagnostics like the square patterns, color bar etc.
 
Also, I picked up an untested 27 " monitor for my mk2 cab (needs work but works) and used my mk1 cab to test it. Other then dark colors there was no shaking
 
i don't remember what screens do it and witch ones don't in those games but i know there are several.

you also need to make sure the +5vdc on your PCB is around 5.1 for MK1 and MKII, they are power hogs and like the voltage a little higher.

you will need to measure your +5 on the 74xx series IC's on your PCB from the top of the board to the bottom to see what it is.

the edge connector and PS don't matter since the IC's are what have to have the proper voltage.

you will often times have a 1-2 volt drop in those games before it gets to the bottom of the game PCB.

you may not have any monitor issues and it is PS related to the game board.

Peace
Buffett
 
Also, I picked up an untested 27 " monitor for my mk2 cab (needs work but works) and used my mk1 cab to test it. Other then dark colors there was no shaking

unless you have a special cab or a conversion, ALL midway MK series cabs were 25"

the 27" will not fit.

Peace
Buffett
 
It fits after modification, long story short I have a 27 flat tube tv in it now to run my pc emutalors and then added a 6 in 1 switcher with mk 1-3 and a video converter only to run into vertical roll issues. So a true arcade monitor is going in. I will check voltages as u have suggested.
 
It fits after modification, long story short I have a 27 flat tube tv in it now to run my pc emutalors and then added a 6 in 1 switcher with mk 1-3 and a video converter only to run into vertical roll issues. So a true arcade monitor is going in. I will check voltages as u have suggested.

terrible, modifying a MK cab:(

as long as you did not hack it up, i guess.

let us know what you find with the voltages.

Peace
Buffett
 
Nothing major, new holes in the monitor brackets to spread them out vertically a bit more and new holes in the monitor frame to fit the studs
 
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