Popeye/Mario Bros. Nintendo Monitor Problem

[froydman]

Hello all, I've got a problem with my monitor.  I've just bought the arcade machine, and am a newbie at this collecting thing, so bear with me.

The monitor for my Mario Bros. game(it used to be a popeye originally, but before I got it, it was modified) does not display the black background any longer, rather all it displays is white.  The game plays normally, and you can see the foreground colors in a manner of speaking, but I think the colors aren't mixing quite correctly.

And I realize the first thing anyone is going to say is "cap kit"...I don't know if that's the problem.  I had it in to a vending supply place in my hometown and they installed a capkit for me which got the machine working(it wasn't working when I got it).  There was a bit of scramble on the screen occasionally(it would flash white instead of black on the background), and they told me about this, but it was very rare.  The very next day though, it became common and then just took over the display.

Any ideas? The monitor is still the original, which through research on the net I believe is a Sanyo 20-Ezv.

Unfortunately, I'm too busy to test out any suggestions in the next couple of days, but I'm interested if anyone has had a similar problem...

thanks!

[SirPeale]

Inverted colors.  It's plugged into the wrong plug on the inverter board.  It's located on the right side of the monitor above the flyback. 

[Ken Layton]

Yes, if this monitor has the optional "inverter" board attached to the top of the metal flyback cage, check the cable is plugged into "non-invert".

[froydman]

But if it were the inverter, would it have played normally for hours, and THEN messed up?

I'm praying it's in the wrong plug because that's going to make fixing it a heck of a lot easier...

[Kevin Mullins]

There was a bit of scramble on the screen occasionally(it would flash white instead of black on the background), and they told me about this, but it was very rare.  The very next day though, it became common and then just took over the display.

Were the colors and such correct before the scramble and white flashing problem?
Does your inverter board have a wire going to the little three pin plug on the inverter board?
The NON-INVERT requires the 12-16VDC power. Otherwise it does nothing.

But I also don't see why Mario Bros. would use this connection, it's a Nintendo game just like what was in there. (Popeye)
It should be INVERTED. (which is really just a bypass of that whole little board other than the three pots on it)

But you may also have a flaky flyback.
Bad solder joints, dodgy connectors, etc. should all be checked.
Even though they should have done all that when they did a cap kit.
(the white screen flash has me curious) 

[froydman]

a bit of clarification here, sorry about not making it clear the first time...

the entire screen didn't flash, just the background would turn white for an instant, though you could still see all the foreground.  As well, the "scramble" would be occasional white bars across the top of the screen coming down about a third of the way...again for only an instant and then it would disappear.  You could still see the game/foreground then as well.

thanks for the advice though, I'll check the machine and get back to you all.

[froydman]

and yes, before the scramble and the white problems the colors were correct.  even now, half the colors are correct, it is the background that is displaying the white instead of the black.  I'll be able to give a more thorough description of the color problems in a few days(I'm out of town now, unfortunately...) but one color I distinctly remember being correct was the red...the demo ran, and the title displayed in the correct color.

that's one of the reasons that I don't think it's an inverter issue now that I think about it....though I could probably be wrong.

[Kevin Mullins]

That's why I was curious if it were correct before it acted up as far as colors go.
The only thing on the inverter board that should effect your picture are the three pots. Otherwise it is just bypassed all together.

I'm thinking you have another issue as well.
Let us know more when you get back to it.

[StephenH]

Inverted Colors:

Red -> Cyan
Green -> Magenta
Blue -> Yellow
Cyan -> Red
Magenta -> Green
Yellow -> Blue
White -> Black
Black -> White

[froydman]

Ok, I'm back home, and I've printed off one of the Mario Pak transfer manuals.

Problem #1:  this monitor doesn't have an inverter.  At all.

Problem #2:  None of the colors is inverted.  The problem is that the background is ALL WHITE.  Every single one of the other colors is correct.  I've tried fiddling with the various color adjustments, and all of them work well.  Again, none of the colors are off/wrong/inverted. 

The problem is that the screen is not displaying the background black, just white in the background.  Everything in the foreground(every color, INCLUDING BLACK!!!) is displaying just fine.

I'm very confused.  Any other suggestions?  Again, this machine worked well for about a day before the white took over the background.

[Kevin Mullins]

Problem #1 - If this is a Sanyo 20EZ monitor and you are running a Nintendo game then it does NOT need the inverter board.
Is it for certain a Sanyo 20EZ? (just to be sure)

Problem#2 - As far as the "white background"..... does the whole screen in general seem overly bright?
Could be the SCREEN voltage from the flyback.

[Ken Layton]

Could even be a bad video rom chip on the gameboard.

[Kevin Mullins]

Yeah..... I kinda was thinking that too, just depending on a better understanding of what was happening. (was just holding off on that one)
If the foreground picture is absolutely correct including the black parts, then it may be a game pcb issue.

A screen pic would be helpful if you can.

[froydman]

Kevin,

I've done some more reading, and I don't believe it's a sanyo 20EZ monitor.  According to both the popeye and mario bros. manuals I've seen, only if the monitor is a sanyo will it have the inverter in the original cabinet.  So, safe to say, it is not a sanyo 20ez.

The screen isn't overly bright that I've noticed.

I'll have a screen shot up tonight.

If it is the video rom chip, what kind of recourse is there, other than replacing the boards?

also, thanks to everyone who's commented, this discussion is helping me learn quite a bit.

[Kevin Mullins]

Is there any marking on the monitor chassis that might help identify it?
(labels, printng, stamps)
The Sanyo 20EZ even has some stamped on the metal frame in a few places.

Take a look at these also:
http://homearcade.org/BBBB/nintendo.html

Sanyo 20EZ in a Donkey Kong
http://www.sventech.com/~dereks/gallery2/main.php?g2_view=core:ShowItem&g2_itemId=1411&g2_imageViewsIndex=1
You can see the inverter clearly mounted on the right side on top of the flyback cage. The audio and control board is on the left side.(hard to see in this pic)

You "may" have the Sharp model or something like that.

If it turns out to be a ROM you could try re-seating them, or it might mean getting a new copy burned for it.

[rzgrip]

Howdy! I have an original Sanyo EZ20 in an original DK machine that does NOT have an inverter board. The 6 pin video cable goes straight fron the PCB to the monitor board. It's not needed.

[froydman]

Hello all, once again.

Item #1: there won't be screen shots.
Item #2: the monitor lacks any english that I can make out.  The only thing that I could see was "made by hitachi".  Again, there are no inverter boards on it.

Item #3: Fixed the problem.  I think I've got some faulty wires going from the PCB to the monitor, or at least faulty connections.  I unplugged, and jiggled them around, checked all the connections, and then plugged 'em back in.  I saw the screen flicker white background, and slowly the black took over again.  Machine looks fantastic now.  The wires were the ones that fed from the game boards into the monitor boards.

w00t!!!

I'd like to again thank everyone for attempting to help me out.

[Kevin Mullins]

Can't say that I have had that problem effect just one particular part of the picture.
Sounds like it could be a simple fix..... I would double check all the solder joints on the connector header pins as weel then.

Gotta love the "wiggle test".
I have found more problems this way than I can keep count of.

Glad to hear you narrowed it down.

[froydman]

well, this machine is definitely a 'fixer-upper'...the cabinet is in pretty rough shape, the joysticks have no rebound in them, the bezel is scratched up...the list goes on.

but it was really cheap.

I think the problem could be narrowed down to this one situation:  Two of the wires fed into the connector come from what looks to be a rush job, someone used a wirenut to connect those two wires with only one coming out of the PCB.  I think that's the part that I jiggled and tightened.  I could be wrong, but it's definitely something that needed tightening up.