Sanyo 20-Z2AW "jail bars"

MaximRecoil

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I'm not sure if this is actually a case of "jail bars" or not:

sanyojailbars.jpg


On the left side of the screen (most noticeable on the boxing ring's "canvas") are a few faint vertical lines. The are actually on the whole screen, but usually they are so faint that the only noticeable ones are on the left. Both monitors in my machine have this same issue, and they do it when being driven by either my Super Punch-Out boardset or my Punch-Out boardset (I don't have a way to test any other boards with the monitors).

I recapped both of these chassis in 2006 using cap kits from Zanen, and it didn't change anything. I recapped the lower monitor's chassis (pictured above) again last night with Bob Robert's "Plus Kit with 9 more chassis caps" thinking that maybe the extra capacitors compared to Zanen's kit would solve the problem (I also replaced the big filter cap last night); but still no change.

B+ (tested after warming up for 20 minutes) is +108 VDC.
 
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It is not screen burn. Both tubes are 100% burn-free (which I recently swapped onto those chassis specifically because they were burn-free).

The same vertical lines were there when displayed on the original tubes too (which did have Punch-Out screen burn, but Punch-Out screen burn doesn't include vertical lines like that). This is what Punch-Out screen burn looks like (these were my original tubes):

poscreenburn.jpg
 
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I was just trying to be optimistic lol. you go over the whole chassis looking for cold solder?

the color drive transistors get especially ugly. after I cap a Nintendo monitor I de-solder the transistors and scrape all the flux shit off with a dental pick and re-apply. I never noticed any other areas that looked particularly bad though.

I'm gonna say this has something to do with the horizontal circuit.
 
I just brought another Sanyo down from upstairs (this one is a 20-EZV also with a recent Bob Roberts "Plus" cap kit), and it has the exact same vertical lines:

20ezv.jpg


I'm beginning to think it is a gameboard issue, because what are the chances of 3 Sanyos all having the exact same issue? I have a 4th Sanyo I can check too (that one still has its original caps and has some geometry issues) ... if that one has the same lines, then I think it is a pretty safe bet that it is a gameboard issue. But then, it would be weird that both my Punch-Out and Super Punch-Out boards would have the same issue. A cabinet issue maybe? Is there anything in the power supply or 120v --> 100v transformer that could cause this?

Edit: Yeah, the 4th Sanyo (another 20-EZV with original caps) does it too (excuse the increasingly crappy pictures; the camera batteries are nearly dead and I can't take the several pictures I usually do just to get one that comes out decent):

20ezv2.jpg
 
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Have you tried adjusting all of the pots on the remote board, chassis and fly? I know you probably have....but I have had a few graphic issues I thought were board related, turned out that the colors and brightness were just messed up.
 
Have you tried adjusting all of the pots on the remote board, chassis and fly? I know you probably have....but I have had a few graphic issues I thought were board related, turned out that the colors and brightness were just messed up.

I did a lot of adjusting with most of the controls on the two Z2AWs currently in the machine after I did the tube swaps, in order to get the colors, contrast, brightness, etc. right. But the fact that all 4 working Sanyos that I have in the house are doing the exact same thing makes me wonder if it is a monitor issue at all. And this and this is interesting. I found those with a quick Google image search for Punch-Out arcade, and they also have vertical lines that are most noticeable on the left. Is this something that is just inherent to PO/SPO machines?

Edit: And another one which also has noticeable vertical lines on the left.
 
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That almost looks like video ringing. Do the bars change with screen content? Are you using the inverter board in bypass mode? Can you see the bars on the gray screen you get when the video input is disconnected?

-Ian
 
Try not using the video inverter board. Just plug directly into the chassis. Just an idea! :)
 
Another thought, looking at the schematics of the game board, there are two capacitors in the video amplifier circuits, one for each monitor output. They are C2 and C3 on the CHP1-BAK board, and are 33uf/16v axial electrolytics. Can't hurt to change C4 while you're there, it's the same kind of cap and filters the sync amplifiers.

-Ian
 
I'm not using the color inverter board with my monitors that are in the machine, nor did I use it when I tested my other 2 Sanyos.

The lines don't seem to change with content, though they are not noticable against some colors.

If I unplug the video signal, I don't get a gray screen; I get no raster at all.

@blkdog7: I believe the first two pictures that I found in a Google image search showing the same vertical lines as my monitors have, are of your machine. Do you still have that machine, and if so, does it still have the vertical lines on the left?

Another thought, looking at the schematics of the game board, there are two capacitors in the video amplifier circuits, one for each monitor output. They are C2 and C3 on the CHP1-BAK board, and are 33uf/16v axial electrolytics. Can't hurt to change C4 while you're there, it's the same kind of cap and filters the sync amplifiers.

Interesting. I wish I had a selection of new capacitors on hand; I'd try that right now. I also wish I had a way of testing one of these Sanyo monitors with a different video signal (i.e., a video signal not from a PO/SPO board). I have a Missile Command, a Double Dragon, and an Ikari Warriors, all with Happ Vision Pro monitors. I wonder if any of their video signal cables would plug right into the color inverter board of a Sanyo (and sync to it properly) without any rewiring? I could use an extension cord to allow the Sanyo to safely get its 100v power from the SPO machine.
 
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Interesting. I wish I had a selection of new capacitors on hand; I'd try that right now.
33uf is a very common value - even if all you have is a radial version, you can replace one of them for a test and make it fit. And honestly, in this circuit, 47uf would be close enough.

I wonder if any of their video signal cables would plug right into the color inverter board of a Sanyo (and sync to it properly) without any rewiring? I could use an extension cord to allow the Sanyo to safely get its 100v power from the SPO machine.

No. You'd have to make up an adapter - the Sanyo video connector is unique to the Sanyo.

-Ian
 
33uf is a very common value - even if all you have is a radial version, you can replace one of them for a test and make it fit. And honestly, in this circuit, 47uf would be close enough.

Yeah, I don't have any new capacitors on hand at all, and no way to get any short of ordering them online. If I do that I'll probably sit down with a PO boardset and write down the value of every electrolytic capacitor on there, and order them all at once.

No. You'd have to make up an adapter - the Sanyo video connector is unique to the Sanyo.

That figures. It wouldn't be a "Not Invented Here" Nintendo otherwise.
 
I have these same monitors in my PC-10, with the inverter boards. why did those come with these in the first place if they're not needed? just another failure point IMO
 
Yeah, I don't have any new capacitors on hand at all, and no way to get any short of ordering them online. If I do that I'll probably sit down with a PO boardset and write down the value of every electrolytic capacitor on there, and order them all at once.

Heh. I guess it's just hard for me to envision not having ANY parts on hand at all.

I wouldn't bother trying to replace every cap on the boardset, just those couple - and besides, I'm not even sure if it's going to help, it's just a thought that *could* cause this problem.

Weird that you get a blank screen - is it completely black, or do you get raster? Some monitors blank out completely without sync, the EZ won't, but I don't know about the Z2AW. These monitors use inverted video, so you can also simply ground one or more of the video lines to turn on that gun - i.e. ground the red pin to get a full red screen, ground all of them to get white.

-Ian
 
Do u have another Nintendo game u can try on the monitor to rule out the chassis?

I have a Punch-Out and a Super Punch-Out boardset. I get the vertical lines on both games.

I wouldn't bother trying to replace every cap on the boardset, just those couple - and besides, I'm not even sure if it's going to help, it's just a thought that *could* cause this problem.

It isn't a bother. There are only 17 electrolytic capacitors on the entire boardset; and they are all grouped and easy to locate. It'll take longer to order them than replace them. I use to work in a PCB factory soldering and/or reworking 1000 boards per night, and I have the same type of equipment at home that I used when I worked there (most importantly a Metcal and an Edsyn Soldapullt). What I unfortunately don't have is an infinite supply of every surface mount and through-hole component imaginable like I did at the PCB factory (nor any supply at all for that matter), nor an HP3070 board tester.

Electrolytics go bad over time, so if I'm going to be working on the board anyway, I might as well replace them all for good measure.

Weird that you get a blank screen - is it completely black, or do you get raster? Some monitors blank out completely without sync, the EZ won't, but I don't know about the Z2AW. These monitors use inverted video, so you can also simply ground one or more of the video lines to turn on that gun - i.e. ground the red pin to get a full red screen, ground all of them to get white.

I don't get anything whatsoever with the video signal cable unplugged; the same thing as looking at a TV that is turned off. I'd have to come up with a way to ground one of the color lines.
 
Heh. I guess it's just hard for me to envision not having ANY parts on hand at all.

I wouldn't bother trying to replace every cap on the boardset, just those couple - and besides, I'm not even sure if it's going to help, it's just a thought that *could* cause this problem.

Weird that you get a blank screen - is it completely black, or do you get raster? Some monitors blank out completely without sync, the EZ won't, but I don't know about the Z2AW. These monitors use inverted video, so you can also simply ground one or more of the video lines to turn on that gun - i.e. ground the red pin to get a full red screen, ground all of them to get white.

-Ian

when I was trying to figure out my "color" issue on the PC-10 after capping I unplugged both and got black screens on both too I'm sure. this is when I realized you have to redo the solder entirely on the color drives.. heh
 
when I was trying to figure out my "color" issue on the PC-10 after capping I unplugged both and got black screens on both too I'm sure. this is when I realized you have to redo the solder entirely on the color drives.. heh

So you're saying that bad solder joints on the color drive transistors will cause a blank screen if the monitor is powered on with the video signal cable disconnected? That seems strange. If the color drive transistors' solder joints are bad, why would the monitor have good color?
 
Nah, only confirming to the world you aren't making up your black screen heh. Throwing some preventative maintenance ideas your way though. Did you say you ran these with the inverter board bypassed?
 
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