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 Post subject: Re: SNES/Famicon PCB Revisions and RGB Video
PostPosted: Fri Sep 20, 2019 3:38 pm 



Joined: 26 Jun 2018
Posts: 9
I posted this on the dejitter thread but I think it's more relevant here:

The more pervasive problem I've faced with my SNES Jr is random-looking background noise in large regions of dark, uniform color. It is worst by far with desaturated colors that are around or below 50% brightness or so. Any brighter and the noise seems to go away (or get washed out) and any dimmer and it's hard to see the noise (but perhaps still there). I have tried a number of solutions to remedy this (changed the caps in my SNES, changed the voltage regulator, added caps to the voltage regulator, used 1st party and recommended switching 3rd party PSU adapter, used outlet without anything else plugged in anywhere near it, used (2 different) isolating transformers for plugging in PSU, tried different capture cards, the list goes on and on). I can upload a video of the noise I'm getting if anyone is curious. It's not noticeable except for in very specific areas, the region has to be a completely uniform color of the nature I describe above, and fairly large of a region at that, for it to be apparent, but it's something I wish I could fix.

I bought my 7374 RGB mod board from RetroFixes and I don't think it has a toggle-able low pass filter. In fact it doesn't look exactly like the Borti/Voultar boards I see most commonly recommended. I doubt that this is the problem, and I'd hate to desolder and replace the RGB mod board to no effect, but if someone thinks the one I used could be causing the noise, I may make that effort. Any other ideas that people have would be greatly appreciated -- I'm willing to try just about anything!

6x oversampling capture, point downscaling to 256 before upscaling:

Image

6x oversampling capture, without point downscaling:

Image

I have tried oversampling less, but my card (Magewell Pro Capture HDMI) won't let me go below 3x oversampling. 3x, 4x, 5x, and 6x all look about the same but for some reason it's easiest to dial in the phase using 6x oversampling, horizontal res of 256 and 512 both look good at 6x, and this still keeps me above my final horizontal res (1184) but within 2x of it. The point downscaling to 256 makes the pixel edges sharper, but seems to increase the visiibility of the noise by quite a bit. Of course, the video encoding washes out the apparent difference a lot -- I will post screenshots of the raw capture when I am back at my setup.

I use 1184x896 for my final resolution, since I find that SNES looks better at a little less than 4:3 and this allows for pixel-perfect vertical scaling and reasonable horizontal scaling (every 8th pixel in the native res image, or 37th pixel in the upscaled image, has a non-averaged boundary).


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 Post subject: Re: SNES/Famicon PCB Revisions and RGB Video
PostPosted: Sat Sep 21, 2019 3:31 pm 



Joined: 08 Mar 2017
Posts: 1105
Super Nintendo's are a little noisy right at the source, but usually the filters in the receiving devices take care of that.
From your description, it sounds like your capture card isn't filtering effectively.
This is odd though, as oversampling is very good at removing random noise.

You should check your THS7374 mod board once more.
The chip has a filter bypass pin that allows you to select a 9MHz filter (otherwise, the full 150MHz bandwidth is being used).

But since oversampling on the capture card doesn't appear to help, it could just be noise that develops on the card itself.


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 Post subject: Re: SNES/Famicon PCB Revisions and RGB Video
PostPosted: Tue Sep 24, 2019 1:03 pm 



Joined: 05 Dec 2012
Posts: 463
@xthechar - That's just analog video noise. The only way to get rid of that completely is to use MiSTer or the Analogue Super NT.


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 Post subject: Re: SNES/Famicon PCB Revisions and RGB Video
PostPosted: Thu Nov 07, 2019 1:59 am 



Joined: 07 Oct 2019
Posts: 19
paulb_nl wrote:
SamIAm wrote:
I also replaced my APU's regulator and have mostly eliminated the big vertical stripe. What I haven't eliminated is a minor amount of diagonal noise. Again, I'd suggest looking at the FF6 title screen instead of LttP, because with all of my modifications so far, I get a perfect LttP title screen yet a slightly fuzzy FF6 title screen. I also still get weird artifacts near the top of the screen when the main FF6 logo appears.


I think the artifacts you are getting is CPU activity noise. Its more easily seen with the OSSC 256x240 optimized mode. I have captured a video with reverse LPF set to max so the noise can be clearly seen: https://youtu.be/syOW-w1q5UA

If you take a look at this video where they visualize the CPU instructions timing you can see the noise looks exactly like that. https://youtu.be/Q8ph2OVqZeM?t=8m18s

There is no noise at the DRAM refresh in the middle where the CPU is halted. Also what they call spinning where the CPU is waiting for something looks the same too with the diagonal lines. Once the game is waiting for controller input at the save file selection the diagonal bars go across the whole screen.


I put a RGB bypass on my GPM-02 and noticed the signature CPU noise. Is there any way to fix it? Thanks in advance.

Edit: In FF6, the noise would normally be a somewhat faint grain but then once you jump into the menu, boom, full blown typical CPU noise graph in the blue background.

I tried the 7805 and S-ENC capping and there was no effect.

Adjusting Reverse LPF to 18 on my OSSC removed the smearing but actually made the CPU noise even more obvious.


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 Post subject: Re: SNES/Famicon PCB Revisions and RGB Video
PostPosted: Sat Nov 09, 2019 12:14 pm 



Joined: 20 Feb 2016
Posts: 290
It might help to add some decoupling caps like they are doing here: https://shmups.system11.org/viewtopic.php?f=6&t=62631

Jailbars and diagonal bars have been confirmed fixed by doing that but I haven't tried it yet on my console to see if it also fixes this CPU noise.


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 Post subject: Re: SNES/Famicon PCB Revisions and RGB Video
PostPosted: Sat Nov 09, 2019 2:44 pm 


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paulb_nl wrote:
It might help to add some decoupling caps like they are doing here: https://shmups.system11.org/viewtopic.php?f=6&t=62631

Jailbars and diagonal bars have been confirmed fixed by doing that but I haven't tried it yet on my console to see if it also fixes this CPU noise.

I wish that thread would get more traction, it really was a marked improvement


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 Post subject: Re: SNES/Famicon PCB Revisions and RGB Video
PostPosted: Sat Nov 09, 2019 5:43 pm 



Joined: 07 Oct 2019
Posts: 19
paulb_nl wrote:
It might help to add some decoupling caps like they are doing here: https://shmups.system11.org/viewtopic.php?f=6&t=62631

Jailbars and diagonal bars have been confirmed fixed by doing that but I haven't tried it yet on my console to see if it also fixes this CPU noise.


I'll get right to that. Thanks!


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 Post subject: Re: SNES/Famicon PCB Revisions and RGB Video
PostPosted: Sat Nov 09, 2019 7:25 pm 



Joined: 07 Oct 2019
Posts: 19
paulb_nl wrote:
It might help to add some decoupling caps like they are doing here: https://shmups.system11.org/viewtopic.php?f=6&t=62631

Jailbars and diagonal bars have been confirmed fixed by doing that but I haven't tried it yet on my console to see if it also fixes this CPU noise.


Put 10uF caps on all major chips and no improvement. However the ones I used were electrolytic ones since I don't have ceramic ones in that value. Will order ceramic capacitors and try again.

Edit: Apparently electrolytic capacitors wouldn't help anyways since it's only suitable for low frequencies. Hopefully the ceramic through-hole ones will do the job. Ordering X7R SMD will take too long atm.


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 Post subject: Re: SNES/Famicon PCB Revisions and RGB Video
PostPosted: Sat Nov 09, 2019 8:32 pm 



Joined: 08 Mar 2017
Posts: 1105
TheJeffChen:
Nothing but ideal capacitors will work here. You want 2-3 10uF SMD caps and I'd also add 2-3 1uF SMD.
The capacitors should be as physically small as possible. Adding leads (or too much solder) already degrades their effectiveness.

Check out the 0306 package here: https://www.allaboutcircuits.com/techni ... tor-types/
Just this wide package alone significantly improves the bypass performance of the capacitor.
If you can get these caps for a reasonable price, pick them!


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 Post subject: Re: SNES/Famicon PCB Revisions and RGB Video
PostPosted: Sat Nov 09, 2019 11:18 pm 



Joined: 07 Oct 2019
Posts: 19
rama wrote:
TheJeffChen:
Nothing but ideal capacitors will work here. You want 2-3 10uF SMD caps and I'd also add 2-3 1uF SMD.
The capacitors should be as physically small as possible. Adding leads (or too much solder) already degrades their effectiveness.

Check out the 0306 package here: https://www.allaboutcircuits.com/techni ... tor-types/
Just this wide package alone significantly improves the bypass performance of the capacitor.
If you can get these caps for a reasonable price, pick them!


Thank you so much for the information.

I tried looking for the one you described on Digikey but nothing came up. The closest one was rated for 4V which obviously was too low.

I did find several 4.7uF 0306 ones rated for 6.3V. Do you think I could stack 3 of these for the same effect?


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 Post subject: Re: SNES/Famicon PCB Revisions and RGB Video
PostPosted: Sun Nov 10, 2019 12:39 am 



Joined: 03 Mar 2005
Posts: 388
I just use a CRT and don't have to deal with the same kind of sensitivity to noise, but I've had good luck getting rid of the infamous vertical stripe and otherwise cleaning up the picture with nothing more than a few pairs of 1uf and 100nf ceramic capacitors near the various chips, and a 100uf OS-CON anywhere on the power rail.

I've heard of people replacing the original 47nf capacitors with 10uf, and that seems risky to me. Large capacitance values don't absorb high frequency (>1MHz) noise as well, ceramic or otherwise. 1uf seems a lot safer in that regard.

One other thing you might consider trying is replacing the 7805. The original ones in SNES/SFC systems are not particularly great quality - they're a somewhat common failure point - and if you also take the time to slap a 330nf-1uf ceramic decoupling capacitor right at the base at the input, it can have a stabilizing effect.

On that note, what are you using for a power supply? If it's a modern switching supply, it could definitely be adding noise. 7805s have poor ripple rejection at high frequencies.


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 Post subject: Re: SNES/Famicon PCB Revisions and RGB Video
PostPosted: Sun Nov 10, 2019 10:52 pm 



Joined: 29 Apr 2016
Posts: 188
SamIAm wrote:
I've heard of people replacing the original 47nf capacitors with 10uf, and that seems risky to me. Large capacitance values don't absorb high frequency (>1MHz) noise as well, ceramic or otherwise. 1uf seems a lot safer in that regard.


The originals are 0.1uF, no? Adding 10uF in parallel with 0.1uF seems to work well in my 1CHIP and SHVC systems.

I've also replaced each 7805 with a 2A 78S05, added electrolytic 2200uF input and 470uF output smoothing caps, plus a ceramic 22uF output smoothing cap (in parallel with the original 1uF). Both systems look effectively noise-free to me now on a 65" LCD.


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 Post subject: Re: SNES/Famicon PCB Revisions and RGB Video
PostPosted: Sun Nov 10, 2019 11:19 pm 



Joined: 08 Mar 2017
Posts: 1105
All these suggestions are good to try.
There's a bit of experimenting involved in this, since you're hunting for best quality out of a really old (and cheap) design.
I'd just like to mention that really large values (2200uF have been mentioned) could create issues of it's own.
I'd recommend staying below an added ~600uF on the output side of the 7805. That value is quite sufficient just from experience.

The original SMD caps should stay in place, with the new capacitors added.
The point is to add additional bypass frequency range over what just the originals provide.
It doesn't have to be 0306 at 10uF (I think that's not quite doable right now). You just want a decent capacity value.


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 Post subject: Re: SNES/Famicon PCB Revisions and RGB Video
PostPosted: Sun Nov 10, 2019 11:37 pm 



Joined: 03 Mar 2005
Posts: 388
copy wrote:
SamIAm wrote:
I've heard of people replacing the original 47nf capacitors with 10uf, and that seems risky to me. Large capacitance values don't absorb high frequency (>1MHz) noise as well, ceramic or otherwise. 1uf seems a lot safer in that regard.


The originals are 0.1uF, no? Adding 10uF in parallel with 0.1uF seems to work well in my 1CHIP and SHVC systems.

I've also replaced each 7805 with a 2A 78S05, added electrolytic 2200uF input and 470uF output smoothing caps, plus a ceramic 22uF output smoothing cap (in parallel with the original 1uF). Both systems look effectively noise-free to me now on a 65" LCD.


They're 0.1uf (100nf) in other systems like the PCE, but I'm pretty sure that in the SFC they're 47nf.

The 7805 datasheet recommends putting a ceramic decoupling capacitor as close to the base of the 7805 input as possible, with the recommended value being 330nf. In reality, this usually isn't necessary unless the device being powered has extreme current fluctuations, but it's still a good idea. Other systems (again, like the PCE) do it. It's definitely a good idea if you're using a switching power supply.

One interesting thing I've noticed is that a lot of SFC boards have an unpopulated capacitor position marked "OS-CON" that would decouple the power rail. It seems like the knew the power decoupling wasn't great, but in the end cheaped out and chose not to use the expensive component. Or maybe they put that there so that repairmen could slap in an OS-CON anytime someone sent in their machine complaining about noise.

Quote:
The original SMD caps should stay in place, with the new capacitors added.
The point is to add additional bypass frequency range over what just the originals provide.
It doesn't have to be 0306 at 10uF (I think that's not quite doable right now). You just want a decent capacity value.


Well, there is perhaps some risk in doing that, if you're using a soldering iron anyway. If you look up the soldering guidelines for small surface mount ceramic capacitors, they'll tell you that you're not actually supposed to touch a hot iron directly to them because it can cause thermal shock cracks. For capacitors already on the board, it's probably not quite as dangerous since the board itself can draw some heat. Best practice, though, would be to either use a heat gun or switch to larger package capacitors with leads, which you would have to lay down on their sides. I did the latter and completely removed the original caps.

https://www.murata.com/en-global/suppor ... c/mnt/0007

Cracked surface mount ceramic caps can short and literally burn up and/or blow your fuse.


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 Post subject: Re: SNES/Famicon PCB Revisions and RGB Video
PostPosted: Mon Nov 11, 2019 3:06 am 


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SamIAm wrote:
Well, there is perhaps some risk in doing that, if you're using a soldering iron anyway. If you look up the soldering guidelines for small surface mount ceramic capacitors, they'll tell you that you're not actually supposed to touch a hot iron directly to them because it can cause thermal shock cracks. For capacitors already on the board, it's probably not quite as dangerous since the board itself can draw some heat. Best practice, though, would be to either use a heat gun or switch to larger package capacitors with leads, which you would have to lay down on their sides. I did the latter and completely removed the original caps.

https://www.murata.com/en-global/suppor ... c/mnt/0007

Cracked surface mount ceramic caps can short and literally burn up and/or blow your fuse.



I've hand soldered dozens if not hundreds of 0805 ceramics, use a reasonable temperature and there is no threat


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 Post subject: Re: SNES/Famicon PCB Revisions and RGB Video
PostPosted: Tue Nov 12, 2019 2:28 am 



Joined: 03 Mar 2005
Posts: 388
maxtherabbit wrote:
I've hand soldered dozens if not hundreds of 0805 ceramics, use a reasonable temperature and there is no threat


I wouldn't doubt that you've had many successes and no failures, and that with good practices - reasonable iron temp, low-temp melting solder, heating the solder pad instead of touching the component directly, etc. - chances are fairly low of running into trouble. However, if you google the subject, you'll find that thermal shock cracking of surface mount MLCCs is both common and a major subject of study, and that hand soldering with an iron is widely discouraged. I can't find it at the moment, but when I was reading about it before, I found a post on an electronics forum by a guy who worked at a capacitor manufacturer who said that a huge percentage of quality complaints from customers turned out to be this.

Also, it's possible for the cracks not to cause shorts. They might simply reduce capacitance, cause open failures, or even do nothing at all. Alarmingly, though, thermal shock cracks have been observed to grow over time, so even if it performs completely all right at the outset, a shock-cracked cap could eventually go bad.

https://nepp.nasa.gov/files/16346/08_00 ... rovsky.pdf
http://www.ieca-inc.com/images/Ceramic_ ... anisms.pdf
https://www.avx.com/docs/techinfo/Ceram ... cracks.pdf
https://www.dfrsolutions.com/hubfs/DfR_ ... esses1.pdf
https://www.dfrsolutions.com/design-gui ... capacitors
https://escies.org/download/webDocumentFile?id=62186

Image

Image


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 Post subject: Re: SNES/Famicon PCB Revisions and RGB Video
PostPosted: Wed Nov 13, 2019 9:31 pm 



Joined: 07 Oct 2019
Posts: 19
paulb_nl wrote:
It might help to add some decoupling caps like they are doing here: https://shmups.system11.org/viewtopic.php?f=6&t=62631

Jailbars and diagonal bars have been confirmed fixed by doing that but I haven't tried it yet on my console to see if it also fixes this CPU noise.


Sad news, this method changed nothing.

I put 10uF 0805 X7R SMD caps on top of all the 0.1uF decoupling caps for each of the major chips, changed the stock 7805 to a 78S05, and put 22uF cap on top of the 1uF output filter. I also put a 10uF on top of the 0.1uF decoupling cap on the Green line (the 2 other colors don't have it for some reason).

Good thing is, the machine is still not broken. I'm open for other suggestions.

I would like to mention that I don't have the diagonal lines, or the jail bar. Just the distinct CPU activity noise.


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 Post subject: Re: SNES/Famicon PCB Revisions and RGB Video
PostPosted: Wed Nov 13, 2019 11:44 pm 



Joined: 08 Mar 2017
Posts: 1105
Do you have a way to enhance the noise and take some pictures?
When I run FF6 menus with a late revision CPU-01, I only see subcarrier related jailbars.
The intro scene shows more noise in comparison.


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 Post subject: Re: SNES/Famicon PCB Revisions and RGB Video
PostPosted: Thu Nov 14, 2019 1:05 am 



Joined: 07 Oct 2019
Posts: 19
rama wrote:
Do you have a way to enhance the noise and take some pictures?
When I run FF6 menus with a late revision CPU-01, I only see subcarrier related jailbars.
The intro scene shows more noise in comparison.


Yeah, I should have posted them the first time. Here are the photos and a video:

https://imgur.com/a/V2QwyWj

https://youtu.be/U4FHDDY6qBw

I applied the reverse LPF and enhanced the noise. It was well visible without the R-LPF, but the camera would have difficulties to show it.


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 Post subject: Re: SNES/Famicon PCB Revisions and RGB Video
PostPosted: Thu Nov 14, 2019 1:25 am 



Joined: 08 Mar 2017
Posts: 1105
I can only suggest you try the RGB bypass filter option if your mod board has it.

The only way on my setup to bring out this noise is to disable the ADC filter and disable oversampling.


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 Post subject: Re: SNES/Famicon PCB Revisions and RGB Video
PostPosted: Thu Nov 14, 2019 1:34 am 


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stacking the caps cleaned up my video 100% but that was on a SHVC-CPU-01, I see you have a GPM-02 which I have no experience with


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 Post subject: Re: SNES/Famicon PCB Revisions and RGB Video
PostPosted: Thu Nov 14, 2019 1:56 am 



Joined: 07 Oct 2019
Posts: 19
rama wrote:
I can only suggest you try the RGB bypass filter option if your mod board has it.

The only way on my setup to bring out this noise is to disable the ADC filter and disable oversampling.


I'm using borti4938's RGB bypass mod. The LPF jumper didn't change anything either enabled or disabled.

maxtherabbit wrote:
stacking the caps cleaned up my video 100% but that was on a SHVC-CPU-01, I see you have a GPM-02 which I have no experience with


I have noticed that GPM-02 rarely turns up in the discussions. I imported this machine from Japan, so it's probably not very common over here. It's also the one with the worst smearing so probably ppl would simply avoid it.

I'm sure some of the stuff I did helped on other aspects, but this CPU noise pattern must be from something different.


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 Post subject: Re: SNES/Famicon PCB Revisions and RGB Video
PostPosted: Thu Nov 14, 2019 2:38 am 



Joined: 03 Mar 2005
Posts: 388
TheJeffChen wrote:
I have noticed that GPM-02 rarely turns up in the discussions. I imported this machine from Japan, so it's probably not very common over here. It's also the one with the worst smearing so probably ppl would simply avoid it.

I'm sure some of the stuff I did helped on other aspects, but this CPU noise pattern must be from something different.


Huh. I have a GPM-02, and on my CRTs at least I couldn't make out any noise. This was when I was checking the amount of noise on an APU board, which was extremely visible by comparison. As an aside, I also didn't notice loss of clarity (smearing) over the APU board.

At this point, it looks like you've done all you can to stabilize the power rail. The source must be something else.

Do you get more noise on any particular RGB channel?


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 Post subject: Re: SNES/Famicon PCB Revisions and RGB Video
PostPosted: Thu Nov 14, 2019 3:43 am 



Joined: 07 Oct 2019
Posts: 19
SamIAm wrote:
TheJeffChen wrote:
I have noticed that GPM-02 rarely turns up in the discussions. I imported this machine from Japan, so it's probably not very common over here. It's also the one with the worst smearing so probably ppl would simply avoid it.

I'm sure some of the stuff I did helped on other aspects, but this CPU noise pattern must be from something different.


Huh. I have a GPM-02, and on my CRTs at least I couldn't make out any noise. This was when I was checking the amount of noise on an APU board, which was extremely visible by comparison. As an aside, I also didn't notice loss of clarity (smearing) over the APU board.

At this point, it looks like you've done all you can to stabilize the power rail. The source must be something else.

Do you get more noise on any particular RGB channel?


The noise is gray-ish. So I guess if it's from RGB, it's on all channels.

I did hear that on actual CRT the noise is much less noticeable. I can't test it right now because my CRT is in the garage and it's way below freezing point outside.

I did take apart the multi AV plug and change the sync from composite video to TTL sync with a 330 ohm inline resistor, but that had no effect on the noise. I'm considering to disconnect all RGB channels and see if the noise is from the sync signal itself.

Edit 1: Nope. Disconnected RGB from the bypass board and I just got a perfectly black image. Guess the noise is still in RGB. Now connecting it one by one.

Edit 2: Noise level G > R > B. Trying a shielded cable now. I've been thinking about this for quite some time...

Edit 3: Aaaand nope. Shielded cable for the RGB bypass board didn't help either.


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 Post subject: Re: SNES/Famicon PCB Revisions and RGB Video
PostPosted: Thu Nov 14, 2019 1:12 pm 



Joined: 20 Feb 2016
Posts: 290
It might be needed to remove the R,G,B signals off the board by removing the closest components to the PPU. Worst case the pins have to be lifted on the PPU.


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 Post subject: Re: SNES/Famicon PCB Revisions and RGB Video
PostPosted: Thu Nov 14, 2019 1:53 pm 



Joined: 07 Oct 2019
Posts: 19
paulb_nl wrote:
It might be needed to remove the R,G,B signals off the board by removing the closest components to the PPU. Worst case the pins have to be lifted on the PPU.


For this RGB bypass I had to replace 3 sets of resistors on the RGB channels on the board and take the signal from between those resistors, according to the guide. Do you think taking the signals directly from PPU2 instead wouldn’t mess up stuff?


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 Post subject: Re: SNES/Famicon PCB Revisions and RGB Video
PostPosted: Thu Nov 14, 2019 2:30 pm 



Joined: 08 Mar 2017
Posts: 1105
It would. The 3 chip SNES RGB path uses transistors for voltage / current steering, so a new signal path into the new amplifier will have to be designed.
Contact yoshiyukiblade. He may be able to help, as he's just done something similar.
memberlist.php?mode=viewprofile&u=20943

Hint: Don't try to just feed the PPU2 RGB into the THS7374 somehow. It won't work :p
Edit: Here's probably the best material you can find on the topic:
https://github.com/borti4938/SNES-AddOn ... 1-reported


Last edited by rama on Thu Nov 14, 2019 2:40 pm, edited 1 time in total.

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 Post subject: Re: SNES/Famicon PCB Revisions and RGB Video
PostPosted: Thu Nov 14, 2019 2:35 pm 


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I certainly wouldn't go lifting PPU pins for this, it doesn't even seem like the issue is derived from noise coupling into analog RGB, but from something further up the chain


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 Post subject: Re: SNES/Famicon PCB Revisions and RGB Video
PostPosted: Thu Nov 14, 2019 3:33 pm 



Joined: 07 Oct 2019
Posts: 19
I do still have some other thoughts.

- Borti’s board used 0.1 and 22 uF decoupling capacitors on the bypass board. Should I try adding a 10 uF one as well?

- When disconnecting the original RGB signal from the multi AV port, I turned the original 47uF capacitors around, jumped the other end a little further up the RGB circuit, and then cut the trace between the pad to the multi AV and the old RGB circuit. Before doing this, I tried:
a) removing the original Q4 Q6 Q8 transistors and connect RGB to one of the feet - I got almost no RGB signal at all, only very faint shadows.
b) putting back the transistors, then there was very bad ghosting, looked like reverbs.

Is it possible that the original RGB circuits now need to be terminated with something like a 75 ohm resistor right beside the final decoupling capacitors to prevent signal reflection?


Last edited by TheJeffChen on Thu Nov 14, 2019 4:12 pm, edited 1 time in total.

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 Post subject: Re: SNES/Famicon PCB Revisions and RGB Video
PostPosted: Thu Nov 14, 2019 3:56 pm 



Joined: 08 Mar 2017
Posts: 1105
PAL or NTSC SNES?

The borti mod board is perfectly fine with the specified capacitors.


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