NESRGB help

[coffeyrt]

Hey guys. I got my NESRGB to work perfectly a week ago in a front loader but it seems it just died. Today I went to use the NES and all I got was a grey screen through the s-video, then a flicker of the game, then back to grey. I then checked the normal composite and I got a blue screen when the board should have been on (is this normal?). Niether one of these was blinking. After checking a few things, I now can't even get a grey screen with s-video, all I get is a blank, black screen. With the normal composite out I get a blue screen no matter what game and whether or not the palette switch on the NESRGB is connected. I checked all of my soldering joints, and they look good. I guess the next step tomorrow would be to take the ppu out and put it back in but it seems if it was working at one point, then the joints should have been good. Are there any additional suggestions? How would I be able to tell if my PPU is dead? Thanks for any input...

[sazyario]

My first guess is a bad PPU
My 2nd guess is a bad 72 pin connector

Have you ever replaced the pin connector? Those replacements are utter garbage.
I have a couple with "death grip". Games wouldn't boot.
I did the boil trick on the original, and the games worked fine. Also, the loading ramp's alignment matters greatly.

[coffeyrt]

Yes it is a newish 72 pin (I replaced it about 10 years ago). I have another new/unused one sitting around I could try and also see if I can find the original. I did try reseating the connecter a few times without any change. If these don't work, I think I am going to remove the PPU from Tim's board, and connect it into the NES PCB to see if I can restore function. Is there a way to test the NESRGB board to make sure that is working? I am a bit nervous about the NESRG not putting out any picture. I'm hoping if the PPU doesn't work I can just buy a toploader and move the board into that...

[CkRtech]

Sorry to hear about your toubles, coffeyrt. Wish you the best of luck!

One thing that might be a longshot - the lockout chip on the NES would typically cause a screen to blink (from black to grey, IIRC). This could happen due to a dirty cart connector or even a lockout chip that went bad. I have no idea if this behavior would be slightly altered when outputting video from the NESRGB (such as blinking between game and grey or even a black screen).

Have you disabled the lockout chip? Does your NES power LED glow solid the entire time despite what is shown on screen, or does it also blink?


EDIT: I suppose it is possible you also have a cold solder joint somewhere on your pin headers on the NES or pins/PPU pins on the NESRGB.

While it is possible the PPU is shot, go for the smaller, less dramatic things first!

[sazyario]

What method/tools did you use to remove the ppu. It's possible you killed it with excess heat.

Nothing to my knowledge will allow you to test the nesrgb without it being with a functional Ppu to my knowledge.

Nothing beats the original cart connector.

[coffeyrt]

the power led stays solid. i have not disabled the lockout chip so i will look into that.

I used a radio shack desoldering iron with lots of flux. This iron does seem to get rather hot but the ppu was out in a very short time. Would the ppu be good for a few days if I killed it though?

So I'm going to look at the lockout, change the 72 pin, and maybe put the ppu back in the nes pcb. I'm not at my place today but I will check these things Tomorrow. Thanks for the input. If you have anymore it would be appreciated.

[Pasky]

Those radio shack irons do not ground you (i.e. they're not ESD safe). It's possible you fried the chip through the iron with an electrical shock. I've actually done this, back when I didn't have a proper soldering station.

[coffeyrt]

Long story short: Installed NESRGB. It worked for a week, then I got a grey blinking screen and no game worked. During troubleshooting I got only a blank black screen and no longer the grey screen. PPU works fine but the NES is dead. I think I ran 10v through the NESRGB during troubleshooting. Is it salvageable?

I think I did the following 2 things. Might have damaged the CPU when trying to solder onto pin 1 and 2 for audio (this was before I read to solder them onto the resistors). I believe that's the case because I removed the board and put the ppu back into the NES and it didn't work, but I now know the PPU is still good. Before putting the PPU back in, during troubleshooting I may have supplied the NESRGB board with 10v out of the input of the NES 5v regulator. This was attached onto the +5 with J3 not bridged. Yeah I know, stupid and at the time I felt like I shouldn't handle electronics anymore...

My ppu is still good. I got another NES, took out the PPU and replaced it with my original PPU from the other NES and it plays fine.

Put the NESRGB into the new NES and back to black screen with no picture. Took the NESRGB out and put the PPU back in the NES (back to stock) and it plays perfectly.

If I put 10v through the NESRGB, is it salvageable? The traces seem fine. Is there something in particular I should be checking that might be replaceable? I just ran 5v through the board and checked the 3.3v regulator. This seems to be putting out 5v on both sides. Is that a 3.3v regulator under J3? Is there something in particular I should check that would go first and is replaceable, or is it just time to get a new NESRGB?

[SunJammer]

I'm having a similar problem with my NESRGB install - I've only connected S-Video but all i get is a solid grey screen when turned on. My PVM recognizes it as an NTSC signal but I can't any picture at all. My first inclination is I damaged the PPU when pulling it from the board - some legs did break off during the process but I was hoping my leg repair would be enough. I'm going to re-check all my solders and put the PPU back in the main board to test but if anyone else has any other things to try I'd appreciate it

[CkRtech]

I'm having a similar problem with my NESRGB install - I've only connected S-Video but all i get is a solid grey screen when turned on. My PVM recognizes it as an NTSC signal but I can't any picture at all. My first inclination is I damaged the PPU when pulling it from the board - some legs did break off during the process but I was hoping my leg repair would be enough. I'm going to re-check all my solders and put the PPU back in the main board to test but if anyone else has any other things to try I'd appreciate it

Did you follow all of the jumper settings (I think you only have to solder one for NTSC)? How did you hook up your palette switch?

[SunJammer]

Did you follow all of the jumper settings (I think you only have to solder one for NTSC)? How did you hook up your palette switch?

I only closed jumper 5, since I'm using the using the extra voltage regulator. For the palette switch I just connected pad 1 to ground, though eventually I intend to use a switch. For a connector I'm using a salvaged snes multi-out, and at the moment I've only connected pins 5-8, 5 and 6 to ground, 7 and 8 to Y and C respectively

[ApolloBoy]

Did you follow all of the jumper settings (I think you only have to solder one for NTSC)? How did you hook up your palette switch?

None of those should create a gray screen though. A gray screen with the NESRGB usually means that the PPU is dead, and knowing how SunJammer removed it I wouldn't be surprised if it got fried in the process.

[CkRtech]

Did you follow all of the jumper settings (I think you only have to solder one for NTSC)? How did you hook up your palette switch?

None of those should create a gray screen though. A gray screen with the NESRGB usually means that the PPU is dead, and knowing how SunJammer removed it I wouldn't be surprised if it got fried in the process.

Ahh rats. I never really bothered with the palette switch "off" for composite, so it was just a guess to get the ball rolling on any possible salvage after the damage to the PPU.

Sorry for your situation, SunJammer.

[SunJammer]

Did you follow all of the jumper settings (I think you only have to solder one for NTSC)? How did you hook up your palette switch?

None of those should create a gray screen though. A gray screen with the NESRGB usually means that the PPU is dead, and knowing how SunJammer removed it I wouldn't be surprised if it got fried in the process.

point taken

[viletim]

A grey screen means the NESRGB is uninitialised. It usually means the CPU is not running - it may have failed.

[Pasky]

May not be the CPU itself, it's possible you damaged a trace from the PPU to CPU or else where. Check continuity between them first using a schematic.

[SunJammer]

A grey screen means the NESRGB is uninitialised. It usually means the CPU is not running - it may have failed.

thanks! I'l check the traces on the CPU, it is possible something took a hit during install