NESRGB colour problem (help Req)

[Monstermug]

Wasn't sure to post this in the NESRGB thread or a seperate thread. As the other thread is like over 100 pages long, I thought it might be better to open a new one in case someone else is having the same problem.

Recently nesrgb my spare NES console. Was working fine for an hour or two then the screen started to flicker between colors and now its gone a complete shade of red.

Before pics:









After pics:







I've tried the following with no effect:

1. Cleaned contacts and re-socket the ppu chip.
2. Checked all connections for cold solder joints and continuity which I doubt there was any but I did it regardless
3. Tried a different game.
4. Checked the scart cable made from the kit from Tim. Nothing really to check tbh. The Scart pcb looks fine but I don't have a spare to test this.
5. Its not the monitor problem I can assure you.
6. Changing palettes does not resolve this problem. It just creates a different shade of red.

Scratching my head atm. Game working but color just went funny all of the sudden.

Any guru's have any ideas of what to try next or what the problem might be?

[Pasky]

Looks like green is missing. Check the green color line.

[Zer0-2k11]

The 220uF Tantalum Capacitor on the "Green" line on the NESRGB Board has probably gone bad, i've heard of some people having issues with the capacitors. Try bridging the ends of the capacitor on the "Green line" and see if it makes any change. Pair of tweezers should work. In this picture, they are black/grey colored capacitors but they could yellow/orange as well.

[Monstermug]

Thanks guys. Just replaced it with another capacitor and it's working fine now.

[zeruel85]

I wanna thank you for this thread, 'cause I had the exactly same issue and I resolved it with the swap of the tantalum capacitor on green signal.

You are awesome! Cheers.

[Supergun]

I’m also giving a thousand thanks for the tip here. I too had the exact same problem as well, where green would fail intermittently, and so I ran a google search and stumbled on this thread. I briefly bridged the capacitors contacts with clips and surely enough it reacted & proved to be a faulty component. I then desoldered the capacitor and soldered in a replacement & the problem went away.

I play tested the console for several hours afterwards and the problem never returned. She’s running perfect now & I’m very happy with having been able to resolve the issue. Thanks again.

Now I’m off to go play Gradius 2. Later!

[tobeder]

Also want to thank you for this thread. I had the same issue and then I bridged the capacitor on the green line and now is working fine. I'll search for the corresponding capacitor in order to replace it.

[tobeder]

Hi, I have like a similar problem but not sure. Recently I fully recapped my NES thinking that this issue could be related to the NES capacitors but later found that this issue could be related to the 220 UF Tantalum capacitor on the NESRGB board. I got this new capacitor replacement but the problem persist.













These are the new capacitor T490B227M006ATE500 specs:





Previously to get my new capacitor I bridged the green line on the board and got good image but now even if I bridge the problem persists.

Other consoles work fine with the same monitor and BNC-SCART JP-21 cable.

Thanks in advance.