NES RGB mod

[Moosmann]

Replace >all< 3 Amps with a 10uF Electrolyt capacitor, very important. You can also use:

BC557 = 2SA1015
BC33725 = BC546

R6 is difference, you can also use a 100 Ohm poth to adjust the brightness. And add a 4,7uF Capacitor (without polarity) between +5V and GND.

Bye Markus

[Bostich]

I think I just figured out the problem!  I had the transistors hooked up backwards.  I just flipped both transistors around on the red amp (the one using the polarized capacitor) and the picture is now crystal clear.

The diagram on the packaging for these transistors is a little confusing, IMO.  It is a straight top-down view of the transistor, but it doesn't indicate if the curved side is up or down.  Apparently the diagram is drawn curved side down.  I originally interpretted it the other way around.

Thanks a lot for all your help Moosmann!  I may try your other suggestions if the picture is too bright once I fix the green and blue amps.  (I only have red connected right now.)

[Guest_Bostich]

For some strange reason, I can't post while I'm logged in now.

[Guest_Bostich]

I get the following error page: "Error 400"

[Guest_Bostich]

I also can't seem to post more than one sentence at a time.

[Guest_Bostich]

Anyways, I finished the NES RGB mod.

[Guest_Bostich]

http://bostich.no-ip.com:81/RGB_mod.html

[Bostich]

I've been noticing a slight issue when playing my RGB modded NES.  It has faint lines creeping across the screen.  These are most noticeable in large patches of solid color.  

At first glance, these lines would appear to be interference of some sort.  However, there is no variation in the spacing or movement of the lines.  When I have seen interference in the past (back when I used to use RF switches for all my systems) it seemed to be fairly unpredictable.

These are horizontal lines moving from bottom to top.  There are approximately 30 lines on screen at a time and it takes roughly 20 seconds for them to travel the height of the screen.

I remember seeing these lines before I had built the amp, so I don't think the amp is introducing the lines.  The lines were a lot more noticeable without the amp.

Has anyone seen an effect like this before?

[Moosmann]

Never on my nes and famicom.

I only notice vertikal stripes lines in some games like Castlevania 2. However, when I play Castlevania 2 on the FDS, it`s no vertikal lines. I think, it is some difference in the cartridges, but I haven`t found out "why" at the moment.

Bye Markus

[Michael]

Can anyone give me some detailed information on the NES stereo mod? I want to mod my NES to have a 1/4" stereo output and would like to have a pot to control the mono-stereo mix. Also, does this mid dropout some of the volume?

I can' find a good resource to learn this mod. Pictures and instruction would be great!

my email is censoredpromo@ msn.com if you have any info or I'll try to check back here.

[kendrick]

Michael, as your question isn't strictly relevant to the RGB discussion, please start a new thread. Or better yet, please use the search function to look for two previous discussions of the NES stereo mod to see if that answers your question.

-KKC

[acem77]

finally got the playchoice 10 ppu for my nes rgb mod!
i used the simple n64 rgb amp to boost the brightness as you can see it works great.
it looks great. i also did the stereo mod and love the new stereo sound.
here are some pics of the nes with out rgb then with rgb hooked up to my samsung dlp through a xrgb2 plus.

thanks a lot Moosmann your help made this mod very fast and simple to do.

composite   :rolleyes:


rgb   B)


stereo sample
stereo_nes.zip


sorry for the repeat bump but i had to make a new post cuz i could not edit my original post.

re-edit fixed the link.

[Richter X]

You put http:// twice in that stereo nes link. ^^

[davidleeroth]

Hi guys,

I've been attempting to do this mod for some time now and it just doesn't seem to working and I ned some ideas.

I've replaced the PAL NES PPU with a RP2C03B, build the amp and all but the graphics are scrambled. I can see the game playing and the picture is stable (not rolling) but it seems like there's about 8 little screens in the picture, everyone displaying a different set of random lines. I don't know how to describe it better, I'll try to get a picture of it soon.

I've done the mod using Moosmann's directions, I've tapped the sync from the RF Unit like in Moosmann's picture. I've tried it with and without 68-120 caps but they don't seem to affect the problem at all. The NES still works well with original PPU.

Any help or ideas would be great.

[DarthCloud]

I might be wrong but i'm pretty sure you need an NTSC nes to do this mod cause pal nes have a special cpu and ppu witch run at a different speed than NTSC NES/FC.

For modding a pal nes with RGB ppu you will need to swap both cpu and ppu and also change the clock.

[davidleeroth]

I might be wrong but i'm pretty sure you need an NTSC nes to do this mod cause pal nes have a special cpu and ppu witch run at a different speed than NTSC NES/FC.

For modding a pal nes with RGB ppu you will need to swap both cpu and ppu and also change the clock.

Thanks, don't know why the thought never crossed my mind before starting the mod.  So I did some quick reading about the CPU's and it seems the US/PAL CPU's have a different divider (12/16) respectively) to achieve the clock. I just was thinking what if I change the crystal to 28,636363Mhz which then would be divided by 16 to get the NTSC clock 1,79Mhz, would that work? Or would I then need a separate clock for the PPU?

Or does someone have a spare NTSC CPU they want to sell me? 

[DarthCloud]

Thanks, don't know why the thought never crossed my mind before starting the mod.  So I did some quick reading about the CPU's and it seems the US/PAL CPU's have a different divider (12/16) respectively) to achieve the clock. I just was thinking what if I change the crystal to 28,636363Mhz which then would be divided by 16 to get the NTSC clock 1,79Mhz, would that work? Or would I then need a separate clock for the PPU?

Or does someone have a spare NTSC CPU they want to sell me? 

How did you get your RGB PPU?, if you get it from an arcade board then you can find your NTSC CPU here. Otherwise just get an US NES of eBay, it would be a lot easier...

Also You really need to swap the CPU, changing only the clock will not work since the CPU is designed to work at a certain speed. So changing the clock for a lower or faster one is likely to fail. And you cannot use two different clock in a system cause clock never really run at exacly the fequence they are rated. So even if you use two clock that are common divider this will not work. Like one of my professor said in my course of digital design: " Don't fuck with the clock"

I don't know if swapping CPU+PPU+Clock will work, maybe the PCB layout of Pal nes is different.

[viletim]

Also You really need to swap the CPU, changing only the clock will not work since the CPU is designed to work at a certain speed. So changing the clock for a lower or faster one is likely to fail.

If the CPU has a higher ratio clock divider inside then increasing the speed of the clock to compensate will result in the CPU running at the correct speed. That's the whole point.

[davidleeroth]

The PPU came with Duck Hunt ROMs so it didn't include the CPU. I did, however, manage to buy a NTSC CPU from a local video game store. Man, that store is amazing.

I'm gonna try to change the crystal to 28MHz first and if that won't work, I'll tackle CPU. It seems though that no-one here stocks either 28 or 21MHz crystals. 

[Moosmann]

@davidleeroth: I have a NTSC CPU & Crystal for sale, please send me an eMail.

Greetings Markus

[acem77]

moosmann seems to have everything
did you every do the rgb 3do mod and put that pcb board i made to use moosmann?
did you check out my post about the powerpak not working correctly with the rgb ppu in my rgb modded nes?
if so any ideas?

[davidleeroth]

@davidleeroth: I have a NTSC CPU & Crystal for sale, please send me an eMail.

Greetings Markus

Thanks for the offer but I already got the CPU and I took a 21MHz crystal from a broken FDS ROM adapter. I see the PC-Engine had one as well.

[davidleeroth]

Ok, changed the CPU and the crystal to NTSC's so now this bad boy is working! The composite picture on the NES had a huge issue with dot crawl and it's all gone now. The improvement is clear in pics but you can really appreciate when there's movement i.e. the first scene of Life Force, which in composite looked ridiculous. I'm very impressed.

The RP2C03 palette does make some games look a bit different, like some Konami games look like they're on MSX but that's to be expected. Games with cartoony colors and graphics like Mega Man seem to come out the best. All in all, the trade-off is well worth it.

Moosmann, I get vertical stripes in some games as well, but they only appear with my RGB monitor. My Sony TV doesn't have even a trace. The stripes are grey on black areas like intro screen in Probotector II.

[Moosmann]

Moosmann, I get vertical stripes in some games as well, but they only appear with my RGB monitor. My Sony TV doesn't have even a trace. The stripes are grey on black areas like intro screen in Probotector II.

It`s normal. I haven`t found a way to reduce these lines. The lines come directly from the ppu. You can compare "Castlevania 2 " Title Screen with Start/Select Screen (last right vertikal line). To get the best quality without grey lines on black areas, recuce the "brightness" on your monitor.

Greetings Markus

[Josh]

Thanks for this info.
I know, "The Immortal" don`t work.
The PPU from "Sharp Famicom Titler" use the same color palette and it is a licensed Famicom.

Bye Markus

If I understand correctly (especially after looking at your website, even though I don't understand German ), the RGB PPUs that are compatible (closest color palette) with the NES are:

--  Any of the Rx2C03x PPUs (available from Vs. Tennis, Vs. Duck Hunt, Vs. Ice Climber (JP), PlayChoice-10, and the Sharp C1 Television)

--  And the RC2C05-99 PPU (available from the Sharp Famicom Titler)

Right?  I hope I got that correct...

Now, I have another question:

Although the color palettes on these RGB PPUs are different from native NES PPUs (RP2C02 for NTSC systems and PR2C07 for PAL systems), between each other, are they all the same?  I mean, is the RGB color palette the same on all of the R-x2C03x PPUs and on the PC2C05-99 PPU?

Please ask if I should clarify my question more...

[Moosmann]

did you every do the rgb 3do mod and put that pcb board i made to use moosmann?

Unfortunately not
I was to busy last year, but I will finish all begun modding projects this year.

did you check out my post about the powerpak not working correctly with the rgb ppu in my rgb modded nes?
if so any ideas?

Yes, I read your posting. I have no idea, but I see this problem with my Action Replay pro.

Right?  I hope I got that correct...

Yes.

I mean, is the RGB color palette the same on all of the R-x2C03x PPUs and on the PC2C05-99 PPU?

It`s the same.

BTW: I use an Iscan HD Videoprocessor/Scaler since 6 Months. I reduce the colors a little to get a little natural colors like the colors from NTSC Video.

Greetings Markus

[timofonic]

I know it's an old post but... anyone managed to solve all this?

http://www.assemblergames.com/forums/archive/index.php/t-15270.html
http://www.disgruntleddesigner.com/chrisc/gotRGB/fctitler.html

[eastbayarb]

Why not just get a famicom titler (yea, i know they are $$$) and mod it for RGB? Wouldn't that work better? Or perhaps consolize a Playchoice board?

[DarthCloud]

All those system use the same PPU so whatever way you use to get RGB from a nes it's alway going to look the same.

[acem77]

I ordered some 200 ohm pots to put in line with the data points on the powerpak.

My plan is to remove all the components from a game genie and use it as a pass through.  Then solder the 200 ohm pots on to the game genie.

i do not feel like messing with/messing up  the powerpak its self.

Does any company sell straight pass though connectors that would work with a nes.  That would be great then i could skip messing with the game genie.


Does anyone know if bunnyboy/ the creator of the powerpak is still alive?
He still has not replied to my email.
I have not asked too much from him. I see this as being very rude if he is choosing not to write back.

[Josh]

Has anyone exactly replicated the color palette of the NES-compatible RGB PPUs for use in an emulator?

Alternatively, does anyone know where I can find exactly which colors are in this "official" palette so I can make a custom palette to use in an emulator myself?

[tsenzen]

Fortunatelly i have an rgb modded av famicom, with stereo that i was able to get from japan for quite a penny, the rgb chip was from a broken titler. The jail bar lines are visible, but doesnt really get in the way if you mess with the settings... I absolutely loooooove it! and it kills me at the thought of anything happening to this gem...

http://bp0.blogger.com/_2N-HuuZ5Otk/RjKXhjBKd3I/AAAAAAAAAB0/o_Uk5wQDMi4/s1600-h/DSC07982.JPG

http://bp2.blogger.com/_2N-HuuZ5Otk/RjKXiDBKd5I/AAAAAAAAACE/reo_PtmffTA/s1600-h/DSC07986.JPG

soo...

after reading through the forums, are any of you guys willing to do this mod for $$$? i have a virgin famicom av that needs modding, and was wondering if any of you guys are interested in doing it?? im not as skilled in soldering to do this job, but was wondering if there are any for sale? even the original US nes is fine by me, please message me thanks, any help will be much appreciated.

tsenzen

[eastbayarb]

If anyone is able to tackle this mod, I have an AV famicom I want RGB modded. Just wonder if my PowerPak will work with it though...

[tsenzen]

Just wonder if my PowerPak will work with it though...

yes the power pak works perfectly, i have to reset every now and then if theres some random horizontal line distortion which is just a powerpak symptom... otherwise than that its a godsend

[acem77]

Just wonder if my PowerPak will work with it though...

yes the power pak works perfectly, i have to reset every now and then if theres some random horizontal line distortion which is just a powerpak symptom... otherwise than that its a godsend

Your power pak works aon a RGB modded NES?
If so i would love to get some info from you!
So far i have had no luck

I finally got around to getting a game genie and gutting it to make a straight through converter.
I cut PPU D0-7 (pins 30-33, 66-69), and soldered 200 ohm pots in between.
It does nothing I can notice. Even When I set the pots all the way to 200ohms
I have tested it in both a RGB and stock nes with the power pak and a retail cart.  Everything works as if the pots had not been there.

Now i need a new idea to try..??

[tsenzen]

since my av famicom is a japanese RGB modded famicom, the pins are obviously different, im using a 72-60 pin converter for the powerpak, which turns the cartridge the opposite direction... but works instantly and perfectly

i did some comparisions between some carts, and noticed that only roughly 1% of quality is changed with feedback noise.. i mean this is very minuscule (your basically sitting 5 inches from the rgb monitor trying to desect the signal) however this doesnt affect the actual rgb.. I realized its the powerpaks interference.

Im using a 20"pvm, and an rgb titler/stereo modded AV Famicom.

[acem77]

since my av famicom is a japanese RGB modded famicom, the pins are obviously different, im using a 72-60 pin converter for the powerpak, which turns the cartridge the opposite direction... but works instantly and perfectly

i did some comparisions between some carts, and noticed that only roughly 1% of quality is changed with feedback noise.. i mean this is very minuscule (your basically sitting 5 inches from the rgb monitor trying to desect the signal) however this doesnt affect the actual rgb.. I realized its the powerpaks interference.

Im using a 20"pvm, and an rgb titler/stereo modded AV Famicom.

What generation of power pak are you using. i am using the newest one.


Does any one here know what the famicom is doing different from the nes.

[tsenzen]

What generation of power pak are you using. i am using the newest one.

i actually have the first run, when the powerpak was just released.. and i am also running the first set of files.. im not sure what has been updated, since i didnt really have a reason to update. i know any non-official, or bootleg versions of games hardly if any ever work..

[acem77]

I just modded a nes for someone else and the powerpak does work on that nes.

The nes that works with the powerpak has a mother board rev nes-cpu-4 and its serial is around 1,280,000.

My nes that does not work has a mother board rev nes-cpu-7 and its serial is
around 11,000,000.

does any one have the real details on how nes serials tie in with the rev of nes mother boards

i just bought a nes that was on ebay.
Its serial is N1,394,910 and it has a Ver 4 Mother board.
The guy was nice enough to take it a part and take pics for me.

i am now looking into a way to make the nes have both ppus on a switch.
i am thinking about using pull-down resistors.

I have used something like this to have 2 switchable bioses in my neo-geo aes system and 2 switchable firmwares in my xbox 360 dvd rom.

Does any one have any idea on the limits the nes ppu may have when trying this?

[acem77]

Son of a bitch 

I just got my new nes with the v4 Motherboard...  it has the same problem with the powerpak
as my v7 MB nes.

I was up till 3am all happy thinking it was going to work with the powerpak just like the last nes i modded with the v4 MB.

I did take high rez pics of the v4 nes that does work with the powerpak.

The main difference I see is in the daughter board with the av,rf and power connections.
There are some small brand name changes for some components.

This v4 nes is the 1st nes I did the does need the cap from pin 24 on the ppu to gnd.


Things I have tried to do when i had the v4 nes that did work with the powerpak.

Switched rgb ppus, cart slots, removed the rgb amp, used the the cap on on pin 24 to gnd.