NESRGB discoloration horizontal bar at top of screen

The short: There is a brownish horizontal discoloration bar at the top of my screen in my nesrgb T.W. 2015 modded toploader.

The Long: I have an nesrgb (toploader) modded by a well respected person who I believe does great work. The mod is for composite, s-video, and rgb. The board is NESRGB14 T.W. 2015 and my output in the back is multiout. Both composite and S-Video work fine.

The cable I am using is the SNES csync multiout SCART recommended by the modder at the time of purchase (I have no idea what resistors are in it). I purchased two (one for my NES and my SNES) and both cables work just fine on the SNES, so at least the cable functions as it should (but maybe not the best choice for nes?). I also tried a sync on luma and it had the same issue.

Other Factors: I know its not an overscan issue, I am using an original power supply. I used to play on a framemeister and didn’t have this issue. However now I play on a PVM and now I see the issue. The framemeister is long gone, so I cannot go back and test it there again. Also, I have not gotten to play much in the last year, so I couldn’t for sure say that the transition is the main problem, although it seems likely and this would lead me to thinking i’ve got some type of resistor issue in my cable. However, I had a bizarre color issue (where the colors would flash to dark and very saturated) with this same mod a few years back, and I sent it back to be fixed. He replaced the color caps, which didn’t help, so then he says he replaced the entire nesrgb board in December 2016. This new board has the same model number as the old board (that color issue was also only present on rgb while s-video and composite worked fine). That makes me nervous it could be other something else and the PMV timing just coincidental, especially because it has been a good 6 months since I touched the nes.
Also, I am using the gscartsw (which works great for all my consoles). I tried switching the sync on and off to no effect. I'll try to go right into the tv later tonight. I already tried different cables and different ports on the switch

Looking for thoughts and suggestions. Especially if the cable is actually this issue, could it have worked fine with the framemeister and not the pvm? Thanks!












Here are pics of the scart cable. I see 3 220 resistors? Not sure if that is good for NES SCART or not!

 

Image link is dead?

Have you tested anything else on the PVM to make sure it's not actually the PVM causing the issue?

Do you still get the horizontal bar when using composite or svideo?

Could you name the modder for us or link us to where you bought the modded toploader?

 

Thanks for the reply! Fixed the image. Also:
1. PVM works great for all other systems (rgb snes, rgb n64, rgb turboduo, s-video gamecube, component wii yada yada)
2. Composite and S video both DO NOT display the gray bar. From what I understand they get there signal from rgb, so I don't get it.
3. Let me get permission for the modder before I post it here. I can tell you that I did not buy the system premodded. I'll add more pics if that helps anything.

 

Some pics of the mod would be good. It does sound like some kind of voltage issue from the cable. Is that bar there with all games? Is it all the time? Does it fade in or out at all?

 

Thanks again. I've added some mod pictures. The bar seems to be there for all games, but isn't visible with all background colors. For instance it isn't visible in the brown curtain on mario 3, but it is on level one where I took this picture. Last night I tested and saw it on all games I tried: ducktales, mario 1, tiny toons 2, and Kirby's adventure. It is there all the time. There can be some flickering of light colored lines to black I noticed in Kirby too. There may also be a very slight roll across the screen from top to bottom the screen that fades in and out that I noticed in Kirby, I'll follow up on this. I need to investigate this more as I didn't notice it in all games. There also seems to be like a very faint horizontal role of darkening that I have only really seen on white.

 

Ok, this mod has been done very cleanly. Although im not a huge fan of those connectors, but its good in this case, because we can pull the connectors off while its running to test some things. like for example.. while displaying a game in RGB, unplug Y and V (grey and yellow) EDIT: My bad, unplug C and Y (Purple and Grey) (this is the s-video connectors) on the NESRGB board. See if that bar is still there.

 

Thanks for the advice! I will test that tonight once we get the kids to sleep. This would be testing for some type of interference?

 

Yeh. Unplugging from the nesrgb is the easiest way, because it doesn't involve desoldering or anything. I do think it's the cable.

In fact, could you show the cable too? and explain how it's hooked up to the PVM.

 

I have not opened up the cable, but it is the retro console accessories snes csync cable. Do I just pop/pry it open? It was the one I was told to buy from the modder. I bought 2 and they both work perfectly on the snes, and both have the exact same issue with the nes. But both used to work with the nes (at least through the framemeister).

The current hookup with rgb is gscartsw (which I also used with the framemeister without issue) to extron to pvm. When I tested composite I went directly into the pvm, as well as on an hdtv and the issue was not there. I also tested s-video through the extron and it worked. I'll cut out the gscartsw just to verify tonight, but that was never an issue in the past. I also tried different inputs in the switch and played with the sync stripper and it didn't fix the issue.

 

The sync stripper wouldn't have made a difference because the NESRGB is using csync already. You could actually just swap the C wire with the CS# wire to use Composite as sync instead of csync, and see if that gets rid of it.

 

I have her composite as sync version of the cable. The SCART head has a screw-like thingy where the cable goes into the head. Just twist it and it will come off. From there, gently open the head with your fingers.

 

...so many innuendos..

 

Monkey: Thanks for the advice on taking apart the cable! Very helpful! I updated the original with pics of the scart cable. There are 3 220s in there, but I don't really know what I'm looking at! Thanks again!

 

They're 220uf capacitors. They shouldn't really be an issue.

I think your scart cable looks fine. I think you should first try connecting to the PVM with as few components between the scart cable and the PVM. If that doesn't change anything, then try swapping the wires on C and CS#, as that will change the csync to composite as sync. If still no good, then I'm not too sure what could be the cause unfortunately, other than something to do with the devices being used with the nes.

Also, what Extron box do you have?

 

Extron crosspoint 128. Could you clarify the swapping of the two wires. Are they the plugs on the new board, or are we talking soldering? I will also try disconnecting the svideo tonight

 

Fortunately for you, the modder made that solderless. Simply unplug the CS# and V (it kind of looks like a U in that font but it is a V) plugs and swap them around.

Have you tried an Extron RGB 201/203 Rxi unit by any chance? I'm no expert but it might help. If not, at least you would end up with a must-have thing for PVMs IMO.

 

I'm hella smart and just realized hey are labeled. Also I can solder... sorta.

 

So I figured it out, and yes I'm a douche. It worked perfectly going directly into the tv, extron to tv, and gscartsw to tv, but not gscartsw to extron to tv. Then I found a small switch in the back of the extron that has 75 ohms and 510 ohms. I switched it to 75 and the issue was gone.

The nes itself directly into the extron had no problem with the 510, but through the gscartsw it needs to be at 75. So that's it...

It gives me a follow-up question. Everything else seems to function fine at the 510, but what should they be switched to? Thanks all!

 

75ohm is the correct resistance level for your consoles. try them all on that value. i doubt you'll need to use 510ohm for your consoles.