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NES RGB mod

Started by Bostich, August 29, 2005, 08:22:17 AM

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FA-MAS

#160
I just performed the RGB mod, exactly as on mooseman's site and I'm having problems.  I'm pulling sync off the yellow RCA jack and RGB from the correct pins off of the Playchoice 10 PPU.  I've got it all running directly to an arcade monitor, no amp yet.  And all i'm getting is white horizontal snow with some color thrown in.  Anyone have any ideas on what would cause that?

Are the 68 or 120 cap required for the picture to be stable?  That's the only thing I haven't done.

Arasoi

Quote from: Hamburglar on October 24, 2010, 01:22:18 PM
That was one of the first things I tried when modifying my 1st version NES for RGB, replacing that cap, didn't do anything, lines were still there.

Good to know. I will try the resistor mod for PPU pin 20/40 anyway and post my results.

Drakon

#162
Quote from: FA-MAS on October 24, 2010, 01:37:53 PM
I just performed the RGB mod, exactly as on mooseman's site and I'm having problems.  I'm pulling sync off the yellow RCA jack and RGB from the correct pins off of the Playchoice 10 PPU.  I've got it all running directly to an arcade monitor, no amp yet.  And all i'm getting is white horizontal snow with some color thrown in.  Anyone have any ideas on what would cause that?

Are the 68 or 120 cap required for the picture to be stable?  That's the only thing I haven't done.

try adding a 100-220 uf  10v cap on the sync line with negative pointed towards the moniter.  Mine wouldn't sync right until I did that.  Either that or you wired something wrong (from how you describe it I think you wired something wrong).

anyway from reading this thread:

http://nesdev.parodius.com/bbs/viewtopic.php?t=601&postdays=0&postorder=asc&start=105

the only people who seem to have found a way to 100% get rid of the jailbars on a model 2 composite mod basically took the parts out of the model 1 that remove the jailbars.  The two parts are a transistor used for amping and a filter.....I'm guessing the filter is what gets rid of the bars.  They only label the filter has is "fc2" on the board and is doesn't say exactly what type of filter it is.  I wish I could find some info on what this filter is and what it does.  But anyway apparently adding these two parts to a model 2 completely eliminates the jailbars on composite video.  So I'm wondering if it would do the same on rgb (except you'd need like 3 of them).

and oh look here's another composite  mod chart with everyone's favourite filter.  "fc2" is here as well.



gonna e-mail darthcloud and ask if he knows

also arasoi on this thread

http://nfggames.com/forum2/index.php?topic=2990.0

moosmann recommends wiring a 220 uf cap between 5v and gnd of the ppu.  Doesn't mention which direction to solder it I assume the same way as that other site so that's something else to try maybe

lol found it again



what are you fc2???

FA-MAS

#163
Quote from: Drakon on October 24, 2010, 10:45:01 PM
try adding a 100-220 uf  10v cap on the sync line with negative pointed towards the moniter.  Mine wouldn't sync right until I did that.  Either that or you wired something wrong (from how you describe it I think you wired something wrong).

There's absolutley no way I wired it wrong.  Remove original NES PPU, place socket with pins 14-16 clipped and wires soldered to them.  Wires soldered to their respective pins on a Jamma Fingerboard.  Sync taken from the Yellow RCA jack also wired directly to it's respective pin on fingerboard.  Verified continuity from PPU pins 14-16 to the fingerboard.  Verified continuity of the rest of the pins to the NES board.

I will try the cap idea.

I built an RGB amp but I think I got a wrong transistor.  I should get video without it right, just weaker?
Rebuilt the green channel of the RGB amp, and I still get the rolling snow, It's just green now.

Also, should the NES act just like an arcade board?  If I only hook up green and sync, I should just get a black and white picture right?

FA-MAS

I went direct, no amp no caps or anything and I adjusted the horizontal and vertical holds on my monitor and I am getting a picture.  Think all I need is a functioning amp?  Would someone be willing to build or sell me one?  Anyone got a link to the ultimarc one if I decide to go that route?


Drakon

#165
anyway I got in contact with darthcloud and he says fc2 is just a ferrite core.  He says it's the entire amp that gets rid of the bars.  I tried running an unamped s-video brightness wire through the nes composite video amp to see if it would clean up the image but it didn't display a picture.  blah

why would green and sync give you a black and white picture?

Also did you try wiring the ground from the system onto your fingerboard at spots like video ground, audio ground?

ahh here we go



ferrite bead

FA-MAS

Yeah, I don't know enough to tell you that if you hook up just sync and green, you still get a picture, only black in white.  It does work though.

I ordered an RGB amp from ultimarc.  I figured it cost less than the parts I'd end up buying to build another one.  I'll wait for it and post my results.

Drakon

Quote from: FA-MAS on October 25, 2010, 09:36:38 AM
Yeah, I don't know enough to tell you that if you hook up just sync and green, you still get a picture, only black in white.  It does work though.

I ordered an RGB amp from ultimarc.  I figured it cost less than the parts I'd end up buying to build another one.  I'll wait for it and post my results.

did you atleast get the picture looking less distorted than the above screenshot?  And also with all 3 colours working?

FA-MAS

It's actually a pretty old monitor.  I'm thinking that's the best it's gonna get on that thing.

FA-MAS

I got my Ultimarc RGB amp and hooked it up.  I'm still not getting any video.  I really need some help with this.

Arasoi

Do you use this Ultimarc amp? (the board on the right)



I don't know about your setup, but the sync on mine needed to be run through a sync cleaner board before it was stable. If you aren't getting any signal at all it's problem a sync issue.

Drakon

#171
fa-mas when I said maybe you didn't wire it right I didn't mean you wired the ppu to the system wrong.  I meant you wired the rgbs and ground to the moniter wrong maybe.  Seriously try wiring up a lm1881 circuit to clean up the sync.  And try adding a 220 uf 10v capacitor to the sync line with the negative connector going into the moniter.  I found that wiring up a lm1881 removes the need for me to wire up a 220 uf cap.  But a small cap is much cheaper than the sync cleaner :P

the issues you describe sound like the moniter isn't getting the right type of sync signal.  Either the signal isn't clean enough for it or it isn't strong enough or maybe even both.

wait....am I the first person who got this working without building a sync cleaner or sync amp?

FA-MAS

#172
I actually already have a sync cleaner that I can try.  I'm also gonna try the caps on the sync line.  And yes I'm sure I'm hooking it up to the monitor right, I'm using a jamma fingerboard and I know the cab is jamma compliant, and I'm wiring to the correct contacts.

Arasoi, yep that's the amp I got.

I was reading up on the ultimarc and the site says it will also amp/filter sync.  So maybe I should try putting sync in it directly from the ppu?

Arasoi

The sync from mine is tapped from the add on board near the yellow RCA jack (sync replaces composite video), it should work tapped off the PPU just fine though.

FA-MAS

Woohoo, got it.  What it ended up being was the way I was testing it.  I wasn't drawing the +5v and GND from the NES itself to power my RGB amp and Sync Cleaner.  Once I did that and tied both of them into those +5v and GND, the magic happened.  Then I hooked it up to my RGB to YUV converter and it's all good.  I see a couple of graphical glitches so I'll have to add the cap.

Thanks for the help guys.

RGB via composite connection



RGB via component



Drakon

#175
fantastic fa-mas that looks soooooooo nice!  You inspired me to try farting around with how stuff is powered since you fixed your system by powering the amp from the console.  So I tried powering my amp from the console and that made the jailbars worse.  Then I tried powering the ppu from a seperate psu outside of the console and that made the jailbars worse too.  Then I wired everything back up.....and added a wire from ppu pin 20 outside of the system.  I kept pin 20 connected to the pcb as well and attached the wire from it to my video circuit and wouldn't you know.....my picture is now 100% perfect and my audio buzzing went away....I have absolutely no idea why this worked.  Strangely enough adding the ground connection from pin 20 of the ppu to my circuit has a different effect on the video than adding the ground from the audio plug.  I figured since pin 20 is connected to the pcb that wiring it into my rig would be the same effect as wiring ground from anywhere on the board.....man was I wrong....

I'm now curious if wiring your amp power on different places on the pcb will have different effects.  And I didn't get a good stable picture until everything was wired into the ground wire of my s-video cable.  So there's a good chance that my jailbar fix only works on s-video

FA-MAS

After I got it working, I was noticing slight jailbars and graphical glitches.  So I put the 68uf cap on and it took away the graphical glitches but made the jailbars a little more noticable.  I'm wondering since you connect the cap between the oe/od line and ground, if maybe the jailbars is actually a grounding issue, or some kind of interference along those lines.

Live_Steam_Mad

Hi, does the NES Powerpak have Save States working perfectly when used with an RGB modded NES / Famicom on the games with supported mappers ?  I ask since a someone has managed to get save states working with some games on the NES Powerpak (normally the NES Powerpak only supports saving your game in games that had a battery backed save feature to start with like Zelda 1, until this guy achieved the implementation of save states) ;-

http://nesdev.parodius.com/bbs/viewtopic.php?t=6024&postdays=0&postorder=asc&start=0

Or does it lead to corruption in the game or other problems?

What a dream it would be... flash cart + save states + RGB + 29" Trinitron / IN76 projector  :)

I got my hands on an "untested" RP2C03B from a PC10 board for a couple of GBP and I have a USA NES coming in the mail with serial number below 1 million, and I'm getting ready to do the mod.

Cheers,

Alistair G.

Drakon

#178
Quote from: FA-MAS on October 30, 2010, 06:27:29 AM
After I got it working, I was noticing slight jailbars and graphical glitches.  So I put the 68uf cap on and it took away the graphical glitches but made the jailbars a little more noticable.  I'm wondering since you connect the cap between the oe/od line and ground, if maybe the jailbars is actually a grounding issue, or some kind of interference along those lines.

yes you're correct it's a grounding issue.  I used to have huge jailbars on my image.  I wired pin 17 of the ppu which is video ground into the video ground only and not into the pcb of the nes.  I also added a wire from pin 20 of the ppu which is general ground to my circuit.  I also left pin 20 connected to the nes pcb.  This has made the jailbars go away.  Strangely powering the ppu from an alternate power source makes the jailbars worse.

oh also fa-mas what model number is your ppu?  I still havn't really seen any graphical glitches from my ppu that I wouldn't get from a normal composite ppu

*edit* okay I did some more testing and it seems that the majority of the problem was attaching video ground to different spots on the pcb.  Keeping video ground wired onto pin 20 of the ppu while keeping that pin connected to the pcb as well gets rid of the jailbars for me and fixes all issues I was having.

Live_Steam_Mad

#179
Wow I just tried my newly arrived NTSC USA NES (I am in England) for the first time before modding it to RGB and boy is there a BIG difference between my PAL NES and this NTSC NES's picture with composite video.

Have a look at the picture below... the first one shows what PAL NES looks like in composite. It's HORRIBLE, nothing like the NTSC version (2nd and 3rd pictures). Note with PAL NES the VERY ragged edges on everything, the sprites being so 'pixel scrambled' that you can hardly appreciate them at all, and there is a herringbone pattern over all the colours. This is the output of my PAL NES, a late board revision version (NES CPU 11, 1987), a Mattel board version, serial number PM694040, model NESE001 (GBR).
Is it any wonder I was so desperate to get a much better RGB picture out of a NES LOL...

In contrast my newly arrived NTSC USA NES is so way better it's shocking. Picture is full screen on NTSC NES instead of having nasty black borders top and bottom on PAL NES, and the music on the NTSC NES (with NTSC USA Super Mario Bros 1) is the right speed (same as arcade) compared to PAL NES  (with PAL UK Super Mario Bros 1) which plays the music too fast. I am getting slightly reluctant to convert the NTSC one to RGB now!

My NTSC NES is serial N0639771, i.e. below 1 million, and has a Toshiba TC74HC373P and all HC and H version chips, no LS ones. Should work with Powerpak when I finally buy one I suppose.

The NES is being displayed here on an Infocus IN76 projector. Any vertical or horizontal lines (very wide spacing!) that you see are a result of my DIY screen made from A3 sheets of paper LOL. NTSC picture is a bit softer than the PAL picture even with the heavy sharpening that I tend to use on the pj settings. On my NTSC NES I see only the tiniest hint of jail bars at all and only on the browns and then only when I see a large area of color. About a 5 percent amount of bars. I wonder how much bars I will see when it's RGB modded LOL. Also I see that the sky in Super Mario Bros is more purple than I would like, on the NTSC NES image, which should go back to a blue on RGB mod I think [later edit: nope, the RGB modded sky is purple on my IN72 projector but blue on my 14" Sony FD Trinitron TV!]

Also included a pic. of my PPU scavenged from a PC10 Single (?) monitor PCB sat waiting to be added. I have ordered the 40 pin socket for the PPU, I bought one like the one on the PC10 board (which was a standard one I think, very tight fit, was rather difficult to remove the PPU, I did it as carefully as I could, levering it out a little each side at a time with a penknife (I have no special tools to do this yet), and I also ordered a Turned pin socket which is the precision version (I think) of the same socket, with 4 connecting bridges of plastic for greatest strength, and gold plated inner for the pins for best contact.

I plan on buying a desoldering iron next. Hope I get the right one   ???

Just thought some of you in NTSC land would like to see what the PAL NES's output looks like... ;D

Cheers,

Alistair G.

Live_Steam_Mad

Rest of pic's ;-

This is my NTSC NES via composite, unmodded.

Live_Steam_Mad

Rest of pic's. No jail bars on NTSC low serial number NES via composite, unmodded so far.


Live_Steam_Mad

#182
My PPU from PC10 Single (?)  monitor pulled out of socket with my penknife, ready to go into my USA NES.

Cheers,

Alistair G.

Live_Steam_Mad

#183
Thought it was important to add here just a few other things for those considering doing what I did and getting a USA NES from overseas... My used PAL UK NES came with a 9V DC (NOT AC) PSU of 2 Amp's capacity (was the power adapter from a BT Home Hub router apparently so it says on the upper side of it!) with centre positive (tip positive) and this PSU's plug fits perfectly in the PAL NES and works perfectly with my PAL NES, tested for many hours, NES does not get above a little warm and PSU stays just a little warm as well. UK NES takes (so it says on it's label) 9V AC 1.3A. I plugged it into my USA NES and it fits perfectly, no problems, USA NES seems to stay the same, getting hardly even a little warm after a couple of hours of use, and again PSU staying only a little warm. USA NES rating is AC 9V 850mA according to it's label. Also the original NES joypads from my PAL NES work perfectly on my USA NES.

When I tried to use my UK Game Genie for NES, with Super Mario Bros (UK PAL game) in my USA NES it didn't work despite many attempts at plugging and replugging. Even though I swapped over my known reliable 72 pin connector from my PAL to my NTSC NES. This seemed to be because you still need to use an NTSC USA game in the GG for it to detect the CIC chip (lockout chip correctly)? Just a guess. Anyway it was either that or connection problems from dirt or compatibility problem due to using UK GG on USA NES. I didn't know. So I ripped off pin 4 from the lockout chip from my USA NES using a medium sized safety pin, then the game loaded in the GG on my 2nd attempt. So I am guessing it was a region lockout issue? Anyway the SMB1 PAL UK game works on the USA NES full screen but the music runs far too fast on the USA NES. Same results with UK game used with GG, or by just the same UK game by itself (no GG used) in the USA NES console. So looks like I do have to buy USA games for it. Also did CIC chip lockout pin 4 removal on PAL NES but it bent my medium sized safety pin so I needed the next size up, and then it worked. I bent the leg of the chip a bit then cracked the leg off the chip with the tip of the safety pin by levering against the body of the chip lengthways (tricky) instead of levering against the other legs of the chip, so as not to break any of the other legs of the CIC chip.

Hope this helps anyone else who is thinking about doing this. Attached is a pic' of my UK mains adapter that I use with my USA NES model NES001.

Cheers,

Alistair G.

Drakon

#184
that's funny my ppu is......white.

anyway since I finally got rid of the jailbars here's some s-video eye candy















looks way better on my tv  ;D

take a look, my ppu is white.  Same thing as what you have?  Mine came from a dual moniter playchoice that says 1986 on it


Live_Steam_Mad

#185
@Drakon, I have 5 of these Playchoice 10 PCB's, I got them all for 3 GBP total (!), they are all untested  :-\, and I chose the worst looking board amongst them to take the PPU from, in fact I just noticed that there is some white coloured powder deposit / dried liquid towards one end of this board around a few components which looks as if one of the capacitors may have leaked or something, I just hope that the PPU is not dead  :-\. However if it is, no great loss for 3 quid.

I was told they were Twin monitor board(s?) but I'm not so sure, I think they are Single monitor versions, I got them off Ebay. I have a feeling that they are boards salvaged by a person who worked at the place where the cab's were and that the cab's were scrapped. Just a guess. Or else how does someone come to have 5 untested PC10 boards to sell?!  ??? Anyway I snapped them up for peanuts.  

I have taken a photo of the board that I took the PPU from, see picture below. It says copyright 1986 Nintendo and PCH1-04-CPU. Serial no. C013507. I have entered the rest of the boards' serial numbers in the KLOV link below (Killer List Of Videogames, Playchoice 10 Arcade machine / PCB Census). The PPU had NO heatsink (I have one other board where the PPU is without a heatsink), reason unknown unless it melted off LOL. The remaining 3 boards have heatsinks.

http://www.arcade-museum.com/game_detail.php?game_id=9043 , it's quite a popular system, and I see the boards and parts come up on Ebay regularly.

I have one board serial C-008239 which has the WHITE ceramic PPU on it like yours, the rest are the same browny purpley mix color (I assume ceramic). The white ceramic PPU is still RP2C03B, with gold legs on the chip. The PPU and CPU and Z80 CPU all have light blue colored sockets on them on this board (it's an early board and an early version of the chip, just like when someone on the forums had a Mostek 6502 white ceramic version chip from early production.

I decided to extract the rest of the PPU's from their PCB's. Actually, I just spent a rather irritating hour or more afterwards unbending the pins on some of the PPU's. When I remove a PPU with my penknife the legs don't seem to suffer hardly if at all, but just noticed as I was extracting the PPU's that one of the PPU's on one of the boards had been mashed into the board by some previous owner / idiot having something pressing hard against the board where it has pressed sideways heavily on the heatsink and even cracked the PPU socket and damaged it quite a bit. I'm still unbending the pins.

Maybe one of these PPU's works and is usable?!  :-\

Cheers,

Alistair G.

Live_Steam_Mad

#186
I don't know how anyone else is taking out their PPU's from their sockets ??? but I used the small blade on my penknife pictured below, the blade is about an inch long. I put the top of the blade (the approx. 1mm thick part) against the very inside of the first few legs and lever the chip up by pressing the knife sideways just a little against the legs and pressing downwards a little against the socket, and lever the chip about 1mm up or less on the left then the right, by pulling up the handle end of the penknife, then repeat, then turn the board round 180 degrees and repeat until the chip comes out. It suprises me how powerful the grip of the socket is on the PC10 PCB, maybe because of heat and it being in so long, I think from a video I saw on Youtube (search for "NES RGB" and it's the first one that comes up) that the "turned pin" type is much easier to deal with i.e. the chip presses into the socket fairly easily with your thumb, but I dread to think how much force I would need to put these PPU's back into their sockets on the PC10 board...

Is there a special tool I should be using specifically for this exact PPU removal task? Anyone got a link?

Cheers.

Alistair G.

kendrick

The PPU is shaped a little funny, but a standard IC puller should do the job. The idea is that you want all the pins to come up at the same time so that they don't get bent away from a straight Z-axis. If you do bend them, there also tools to straighten them.

"IC Puller" on Google has this link right up top, and I'm sure there are other vendors where you live:

http://www.futurlec.com/Tools-IC.shtml

Drakon

#188
I used one of those small flat head screwdrivers.  Just took my time and it came up no problem.  The pins on the rgb ppu are MUCH stronger than the composite ppu pins.  Yeah my playchoice board has the blue sockets too.  Guess I got an older one.  Anyway did a bit more testing today and disconnecting the pin 20 wire from my s-video ground almost had no effect on the picture.  So I guess that maybe fixing the jailbars just has to do with what part of the pcb you wire video ground to? Maybe..

Arasoi

Allright, so I got in a set of 1000uf caps and tried the jailbar trick on this page:

http://jpx72.detailne.sk/modd_files/fc/avmod.htm

I had my doubts as this was meant for composite video, and unfortunately they were well founded as the cap had no effect on the jailbars.

Since the jailbars on my unit really are hardly noticeable I think I will end experimentation at this point and work on something else, namely adding the Famicom's 15 pin accessory port into my NES.

Drakon

#190
darn.  Thanks for taking the time to test this out.  I'm pretty convinced that the best solution for jailbars is how you have things grounded.  When I rewire my grounds the picture noticably changes

*edit* okay so I picked up a copy of kirbys adventure and noticed some stages on it had weird glitches (bottom menu was moving up an down heavily).  So I tried some rewiring.  I made ppu pin 20 my video ground.  Ppu pin 17 I wired into my sound amp ground just because the picture was mega messed if pin 17 was grounded into nothing.  I kept audio ground from the system disconnected since wiring a ground from ppu pin 20 into my video circuit grounds audio anyway and connecting audio ground from the rca jack makes the picture worse for some reason.  Doing this got rid of all the video glitches and the picture noticably improved.  The jailbars and various other picture issues seem to be completely caused by how my grounds are wired.  I'm gonna keep trial and erroring this and make a diagram of how my system grounds are wired once I'm done.  The more I mess with the way things are grounded the better the picture becomes.  That includes jailbars as well as various other video glitches/messed up effects depending on what's happening.

*edit* sorry for the delay in my progress I've been busy doing a commissioned nes rgb mod.  I have improved things since I last posted will just have to wait for updates.  Meanwhile check out my project log for comparison screenshots!

http://nfggames.com/forum2/index.php?topic=4225.0

*edit*

Today I wired my custom amp into the nes power and it doesn't work right at all.  But it works fine from an external psu.  Weird.

FA-MAS

Looking to sell off my RGB modded NES if anyone's interested

Live_Steam_Mad

#192
BTW I finally received my "standard" 40 pin IC sockets for the PPU (to be used as an alternative choice to the turned pin ones that I already have, depending on which I prefer) and the fit is lovely, just a nice moderate insertion force only needed, and looks to be a very good contact (contacts on both sides of the pin). All my sockets have gold contacts / pins. Unfortunately the seller's picture did not match the socket and I was expecting 3 cross braces on the socket (one in the middle) but mine only have 2, one at each end, so the socket bends easily  :-[

I did one half of the "stereo" audio mod and it was nerve wracking so the other half will have to wait for a bit. My desoldering iron came from Maplin but it was 30W not 40W like they told me, so I have to return it. I have a 50W normal iron which works very fast and I don't want to heat up the board for a prolonged time with the low power iron...

My NTSC NES with early serial no. below 1 million seems to glitch every couple of minutes in my newly aquired first NTSC NES game (Super Mario Bros 1 revision A) i.e. the screen glitches but it's like a vertical blank problem and only lasts a fraction of a second and the game plays perfectly and is reliable otherwise and finally the music is playing at the correct speed compared to the PAL version.

Cheers,

Alistair G.

Jibbajaba

Alistair,

Could you go into more detail about the glitch? I'm having some problems with my NES as well, but I am not sure what you mean when you say "vertical blanking".

I've been trying to catch my NES doing it so that I can record it, but it doesn't happen often enough.

Thanks,

Chris

Drakon

#194
okay so I've been rgb modding another nes and made some interesting discoveries.  Yes it had jailbars, yes I got rid of them by my patented re-wiring of the video grounds.  But here's the strange thing, after I made the amps/encoder board run off of the nes power I had to re-wire my grounds to make the jailbars go away and the picture very nice and clean.  The ppu in this system is the darker coloured one (not the white one) and the nes pcb looks a little different from the first one.  So there might not be a 100% perfect way to wire video grounds that will work on all systems and ppus.  But luckily re-wiring grounds so far has fixed all combinations of ppus and nes you just have to do some trial and error.  I've discovered that you need to connect all of your video circuit grounds either to ppu pin 17 or ppu pin 20 making sure that ppu pin 17 stays disconnected from the nes pcb.  I can tell you what I know so far....

Keeping ppu pin 17 seperate from the nes pcb doesn't at all affect how the ppu runs.  Also using this pin for ground on different parts of your video circuit really does help clean up the jailbars as long as it's kept seperate from the nes pcb.  So keeping ppu pin 17 seperate from the nes pcb is very important.

Keeping ppu pin 20 attached to the nes pcb is necessary.  Grounding parts of your video circuit to just a regular ground connection on the edge of the nes made the jailbars worse.  But grounding video amps/encoder boards to ppu pin 20 instead of another spot cleans up the jailbars.

Using the nes to power amp/encoder boards changes the way that grounds need to be wired up.  But for anything on your video circuit like general video ground, rgb amp, amps for s-video/encoded signals, and rgb to s-video/component encoder boards you SHOULD attach the grounds of these components to either ppu pin 20 or ppu pin 17 to clean up the video jailbars.  Also keeping audio ground disconnected might help the jailbars.

I really hope this helps people who have annoying jailbars.  I've only done these fixes on a system that's being encoded to s-video and havn't tested it on a rgb screen.  Doing this won't 100% get rid of the jailbars but it gets rid of about 95% of them basically to the point where you really can't see them anymore.  Also it fixes other video issues I came across like a bright white border on the right side of graphics.  And in some cases a dark smear on the right side of graphics.

oh and ps.  Don't run the ppu off of a seperate power supply from the nes this just makes the jailbars go into full blown insanity  ;D

duo_r

I am doing the NJM2267 circuit on a Turboduo and quick question. Everything on my PCB is sharing the same ground, is that sometimes a bad idea? I am just wondering if this is the cause of my jailbars and ghosting in my circuit. I am more wondering if it is necessary to split up the ground rails (although ground is ground so it shouldn't matter). I am also going to try and connect my ground to a different part of the PCB (although I have no idea why this would affect jailbars, unless there is alot of interference near there?).  ???

Live_Steam_Mad

#196
Quote from: Jibbajaba on December 08, 2010, 08:11:38 AM
Alistair,

Could you go into more detail about the glitch? I'm having some problems with my NES as well, but I am not sure what you mean when you say "vertical blanking".

I've been trying to catch my NES doing it so that I can record it, but it doesn't happen often enough.

Thanks,

Chris

Certainly, sorry it took so long but I only just got round to filming it with my Sony PC110E video camera and then converting it. Here is what I am seeing ;-

Graphics glitch on USA NTSC NES with NES SMB 1 Rev. A, NES serial no. below 1 million

The rolling horizontal line is of course an artefact of my camera / TV interaction and is not the glitch itself. Read on LOL.

This is the Graphics glitch on my USA NTSC NES with NES Super Mario Bros. 1, Rev. A, i.e. USA region NTSC version of this game, my NES has serial no. below 1 million, actually N0639771, it's a revision 4 (NES-CPU-04) PCB. Look at 0:12 seconds in and 0:14 seconds in, there is a very brief black and white horizontal "stripe" half way up the screen in the middle, one mario height above Mario himself. Maybe a "vertical blanking" problem associated with the PPU? Not even sure what I mean myself really. This NES has a Toshiba TC74HC373P and all HC and H version chips, no LS ones. You are looking at the Composite output of the NES going into my Sony 29" KV-29K5U Trinitron TV with maximum sharpness on the TV. I thought at first that it was happening only with my Game Genie but it happens without it, as shown here.

The glitch is sometimes repeatable when you jump up at certain positions (well it's a bit transient even then!) and seems to happen once every minute or so (maybe less). It's quite annoying. Maybe they fixed this with a later PCB? Come to think of it, I don't remember ever seeing this on my late PAL NES with SMB 1 from SMB / Duck Hunt cart.

Here is a picture of my PAL PCB, and next post a pic' of my NTSC NES that has the glitch.

Does yours do this as well? Or is your glitch a different one?

Cheers,

Alistair G

Live_Steam_Mad

Here is my USA NTSC NES that glitches.

Cheers,

Alistair G.

Drakon

#198
Quote from: duo_r on December 14, 2010, 05:47:27 AM
I am doing the NJM2267 circuit on a Turboduo and quick question. Everything on my PCB is sharing the same ground, is that sometimes a bad idea? I am just wondering if this is the cause of my jailbars and ghosting in my circuit. I am more wondering if it is necessary to split up the ground rails (although ground is ground so it shouldn't matter). I am also going to try and connect my ground to a different part of the PCB (although I have no idea why this would affect jailbars, unless there is alot of interference near there?).  ???


the njm circuit do you mean njm video amp?  The video amp should have all grounds connected.  I'm confused.....do you plan on using this amp on a rgb nes?  Because this is the rgb nes mod thread not the turboduo thread.  If you mean jailbars on a rgb nes then worry not.  As I've been telling the rest of the internet my rgb nes had jailbars with no amp attached to it so obviously your amp isn't the cause of jailbars.  Like I stated in the above post it has to do with the wiring of the grounds of your video circuit.  Once I rewired my grounds magic happened and jailbars disappeared.

live_steam_mad: how often does that glitch happen?  I don't have any nes models that're that old so I can't see for myself

*edit* okay I just made the njm amp from the wiki and man what an awesome amp!  It's the perfect brightness

panzeroceania

where can I get a good RGB PPU? I know they come out of playchoice, vs, titlers,

was it also included in the Sharp Famicom TV?

in any case, I'm having little luck on ebay or auctions.yahoo.co.jp I saw a kit on yahoo auctions japan yesterday but somebody sniped me when I was sleeping.

I also found this site,

http://homepage3.nifty.com/F-LABO/ProductsList.html

now do you need a specific type of Famicom or NES for these to work?

I have several Famicom Twins right now but nothing else. From google translate it seems that that guy sells kits for AV Famicoms so should I pick up an AV Famicom? or could I work it into one of my Famicom Twins (I would rather work it into one of my existing consoles)

I also found this site

http://moddedbybacteria.freeforums.org/the-rgb-nes-t994-10.html

and this site

http://baku.homeunix.net/RGB/RGB_FC/RGB_FC.html

so again, if anyone has any ideas on where to buy NES RGB PPUs that would be great, I am thinking that guy in the first link is selling kits, and I'll buy one from him, but I want to know if those will only work with AV Famicoms.

Thanks