Screen jitters, measuring B+ 25" K7000

No way, that's going to far haha, 25 inch can go back in easy. My stepson's 97 Blitz is also running a 27" monitor. So I'm looking the board over for the 74xx IC and have not located them
 
No way, that's going to far haha, 25 inch can go back in easy. My stepson's 97 Blitz is also running a 27" monitor. So I'm looking the board over for the 74xx IC and have not located them. Also might g if I knew what IC stands for :D
 
IC = integrated circuit.

you want an IC that starts with 74, it will have other #'s and letters after that printed on it.

there are lots of them on the PCB.

Peace
Buffett
 
Ok, I have found them, lots of them. I was looking at the white print on the pcb itself instead of the circuitry. Lots of legs on those IC's so I'm not sure where to touch my multimeter leads to.
 
Sweet, I'll look at it tonight and test tomoorow. Thank you very much. This is probably the problem. The k7000 in the mk cab has a midway serial number on the frame that matches the cab serial so I'm sure it worked correctly at one point in its life
 
no prob on the help.

keep us posted.

lets hope it is a simple fix with a voltage adjustment.

Peace
Buffett
 
Ok voltage leaving the PS was at 5.14 vdc. I checked three random 74xx IC's and all three checked in at 5.05 vdc. Cranked up the power supply just a bit to 5.21 vdc and same three IC's checked in at 5.12 vdc. No change to my monitor issue.
 
ok, i would turn down your +5 on the PCB to between 5.0 to 5.1 when it hits the bottom and call it good.

as for the chassis, you may need to send it in if you cannot figure it out, i can look over it to see if i find any issues.

it could also not have a problem with any other game but your MK board.

i have see this before and when the chassis was swapped out, the game ran fine.

i put the other chassis in another game and it ran fine.

i know some CAPCOM games have this same issue, they would play fine with some K7000's and not others even tho there was nothing wrong with the chassis.

this may also be your case.

you will need another K7000 to see if the problem stays or follows the current chassis.

if it fixes your issue, i would just leave it as is and use the other chassis as a backup or for another game.

Peace
Buffett
 
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ok, i would turn down your +5 on the PCB to between 5.5 to 5.1 when it hits the bottom and call it good.

as for the chassis, you may need to send it in if you cannot figure it out, i can look over it to see if i find any issues.

it could also not have a problem with any other game but your MK board.

i have see this before and when the chassis was swapped out, the game ran fine.

i put the other chassis in another game and it ran fine.

i know some CAPCOM games have this same issue, they would play fine with some K7000's and not others even tho there was nothing wrong with the chassis.

this may also be your case.

you will need another K7000 to see if the problem stays or follows the current chassis.

if it fixes your issue, i would just leave it as is and use the other chassis as a backup or for another game.

Peace
Buffett

turn down your +5 to 5.05vdc to 5.10vdc is what buffett wanted to say not 5.5vdc that was missing a critical 0.;)
 
I do have another k7000 that has some chassis issues but can give me a picture. Should I try the current chassis we are dealing with on the other tube and test?
 
I think this is an issue with the midway stuff and k7000s. I just put together a k7000 for a NBA maximum hangtime. It was missing the whole monitor. When I run the NBA board it has a slight jitter left to right to it also. When I throw my 4 player xmen board in the cab there are no issues at all. I just capped and Fly'dthe chassis. I have another couple of k7000 so I will swap those in and see if any of them are better. Does you k7000 have the little satalite board attached to it? Mine does, wondering if that has something to do with it. Post up a pic of your chassis. Here are a few videos I shot of the jitter, I'm not sure it shows up well but worth a try. Does yours look like this?

https://youtu.be/9-8Y9D-CRlk
https://youtu.be/OztvKV9KSGU
https://youtu.be/X06E3Q8Ktm4
https://youtu.be/YDq4k2j0ksE
 
I think this is an issue with the midway stuff and k7000s. I just put together a k7000 for a NBA maximum hangtime. It was missing the whole monitor. When I run the NBA board it has a slight jitter left to right to it also. When I throw my 4 player xmen board in the cab there are no issues at all. I just capped and Fly'dthe chassis. I have another couple of k7000 so I will swap those in and see if any of them are better. Does you k7000 have the little satalite board attached to it? Mine does, wondering if that has something to do with it. Post up a pic of your chassis. Here are a few videos I shot of the jitter, I'm not sure it shows up well but worth a try. Does yours look like this?

https://youtu.be/9-8Y9D-CRlk
https://youtu.be/OztvKV9KSGU
https://youtu.be/X06E3Q8Ktm4
https://youtu.be/YDq4k2j0ksE

from what i see in your videos is normal.
that is the programming type movement i am referring to.

i have all the MK's, JAM in 2 different cabs and they ALL have what yours is doing in the videos the JAM in one of my cabs is running on 2 Nintendo Sanyo's, and it does the same thing.

i have never seen any of those games not do that in ANY cab i have ever seen them in, dedicated or not.

if you look close, it is the flicker of the words that makes it look like it is jumping around, they are not directly layered on top of each other and the strobing effect it generates looks like movement.

Peace
Buffett
 
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.
 
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I'm officially in agreement with buffet not that I actually thought he was wrong ;). I have tested three additional boards in the cab. X-men, sunset riders, and mk2 the midway boards have a jitter to them by design.
 
Dr willy, what about when your in diagnostic mode for mk2. Does it behave the same?
 
I haven't been in the options menu I will try that later tonight. It did do it when it was reading roms on boot up though.
 
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