Mario bros graphic errors/ Sanyo EZ20 issue?

sk8ersublime

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So I replaced the DMA on my Mario PCB and that fixed the missing sprite issue after a lot of double checking and cursing.....

Anyway, I noticed a few graphical artifacts on the screen that seem to get worse the longer I play.

In the first video, you will see the screen flicker every now and then with a line in the black. Not recorded, I also noticed the Level indicator in the lower corner flashes a bit, and I noticed on the bonus levels, the coins have 3 flickers next to them.



In the second video, this happens if I play the game for a bit 15-30 mins, then turn it off and then back on right away. It will stay like this until I leave the game off for a while. I have not timed how long it needs be remain off.



Any ideas?

Thanks!
Chad
 
Looks like you are losing video ground, if it was full sync loss then you would not be able to see any structure in the garbled mess, unless the videoing of the fault "tidies" it up a bit.
 
Looks like you are losing video ground, if it was full sync loss then you would not be able to see any structure in the garbled mess, unless the videoing of the fault "tidies" it up a bit.

But what would cause this to happen after it works fine? Something on the monitor? the board? I am thinking it might be the monitor, just from the way it looks/sounds/feels.
 
It could be a bad ram chip flaking out after it warms up. I would do a deluxe cap kit on the monitor regardless.
 
It could be a bad ram chip flaking out after it warms up. I would do a deluxe cap kit on the monitor regardless.

No and no, bad RAM would not cause a loss of sync or video ground, and what is it with cap kits on KLOV, anyone would think they were the magic cure for everything - they aint.

I would rule out connection problems first, clean the edge connector etc etc. Even slight temperature fluctuations can cause issues with bad contacts.
 
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uh, did you bother adjusting the hold? there are instances where they can be a hair off and you'll have a picture one second and a jumbled mess the next.

I'd hunt for cold solder on the monitor chassis, completely unrelated to your graphic glitch. post-cap kit on these Sanyos I've observed lots of strange shit happens probably cause you have electronics running full throttle again and commonly you'll find you lose primary colors or you could even potentially lose sync, I don't know.

I'd reflow the color drive transistors on the neckboard and do the video input header, just to be safe. it looks like you did your B+ already, which should be 108V.

your board issue, as mentioned, is probably caused by a chip that's getting hot after the board's been on awhile. they make that electronic freeze spray, where you spray certain types of chips you're hunting (in this case, probably look for RAMs after the DMA work you've already done) and when you get the one that makes the glitch go away, you know what to replace!

also unrelated, I find it entirely bullshit that I've made 2 threads about my Mario Bros. board doing roughly the same thing yours did before you replaced your DMA and not one person wanted to help me. whatever.
 
uh, did you bother adjusting the hold? there are instances where they can be a hair off and you'll have a picture one second and a jumbled mess the next.

I'd hunt for cold solder on the monitor chassis, completely unrelated to your graphic glitch. post-cap kit on these Sanyos I've observed lots of strange shit happens probably cause you have electronics running full throttle again and commonly you'll find you lose primary colors or you could even potentially lose sync, I don't know.

I'd reflow the color drive transistors on the neckboard and do the video input header, just to be safe. it looks like you did your B+ already, which should be 108V.

your board issue, as mentioned, is probably caused by a chip that's getting hot after the board's been on awhile. they make that electronic freeze spray, where you spray certain types of chips you're hunting (in this case, probably look for RAMs after the DMA work you've already done) and when you get the one that makes the glitch go away, you know what to replace!

also unrelated, I find it entirely bullshit that I've made 2 threads about my Mario Bros. board doing roughly the same thing yours did before you replaced your DMA and not one person wanted to help me. whatever.

I have reflowed almost everything on the monitor chassis when I Did the cap kit. I did the neckboard as well and the flyback circle.

I think I saw your old thread when I was looking for a fix and I noticed no one responded which made me nervous that there was no fix for the issue. Sorry man :( did you replace the DMA on your board to fix your sprite issue? I'll check out that freeze spray. I had issues replacing the DMA I just hope it's not related to that chip otherwise I'm just gonna look for a new board.
 
I dont know about the first video, but the second one is most def a h-hold problem. My Playchoice was doing that on the top monitor after 15-20 minutes of play. I just touched the h-hold pot and the problem was resolved.
 
I dont know about the first video, but the second one is most def a h-hold problem. My Playchoice was doing that on the top monitor after 15-20 minutes of play. I just touched the h-hold pot and the problem was resolved.

Is this pot on the chassis or the remote board? I have replacement pots for the remote board that I haven't replaced yet.
 
also unrelated, I find it entirely bullshit that I've made 2 threads about my Mario Bros. board doing roughly the same thing yours did before you replaced your DMA and not one person wanted to help me. whatever.

You threads were shortly after I moved and I wasn't on the forum much at all during that time. That's my reason for not responding to them.

RJ
 
Nevermind, I replaced vr301. I played with the h hold and I was able to recreate the screen. I got it back to normal, hopefully it will stay that way. I've been playing a lot this morning and it seems to be staying when I turn it off then back on.

I cleaned the legs and reseated all the removable chips on the board, still have the graphics glitching
 
Thanks for the H-HOLD tip, i left the game on for just over an hour, turned it off and on multiple times, and the picture is normal still.

I still have the glitching though, part of me thinks that the DMA might have a loose connection since all of the glitches are happening on the sprites which were missing before replacing the DMA. I am kind of afraid of messing with the DMA again because I had to remove it multiple times.

Question....the only pins on the DMA i am not sure about having a solid connection are the pins that line up against the Z80A. How am I suppose to get solder on the pins on the top of the board on that side when the other socket is lined up right against the chip?
 
So I resoldered the DMA and I still have the graphic glitches. I have them at boot, but it gets worse the longer I play. It seems like the bottom pipe and level counter start flickering, and they faintly show up in the black on the 2nd platform. Should I look at the CPU board or video board?
 
Get a can of freeze spray at Radio Shack and use it to cool down chips a few at a time until you find the area of the board that changes with the temperature drop. :)
 
Get a can of freeze spray at Radio Shack and use it to cool down chips a few at a time until you find the area of the board that changes with the temperature drop. :)

I the freeze spray the same thing as turning canned air upside down? Lol. I have plenty of air already.

Since I don't have a test bench im working in the cab, do i have to have the game plugged into the filter board? Or can I plug the harness directly to the board? I just do not want to fry anything.
 
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