NESRGB board available now

[Quantum]

Oh hey! Thanks for the responses to my problem.

If you're feeling like experimenting, try connecting each of the RGB signals before its coupling capacitor (yellow thing) on the NESRGB board. It's possible that one of them is bad. It can run without them temporarily, but its not safe to run it like this for long periods of time as the video encoder will overheat.

I can try this tonight.

Did you try a different pair of RGB SCART cables? I saw this before she using cheap cables that were not correctly made.

I am using 8 pin mini din to SCART from RCA with the coax upgrade with the hopes that it would fix this problem.

Another idea is the power supply. Are you using original nintendo do power supply or some cheap switching power supply that adds noise ??

Using OEM power supply, I only have one to test with though.

Is your audio running separately or in the same cable?

Same cable but it is coax upgraded

post pics of install job.

I will tonight.

If you've got caps in the cable, try without them. The NESRGB already has 220uF caps in the output chain. This looks like a DC offset from a line carrying into H-blank, which is slightly affecting your clamping values.

Both the Garfield and Super Mario Bros pictures look this way.

I haven't opened the cable up personally, but RCA told me that this particular cable has no passive components on the video lines. I can check tonight.

The only thing I would have done differently is skip the external power regulator.

With my install I skipped the external reg, also I've replaced the 7805 with one that can handle more current (1.5A I think?) as I also use a PowerPak.

I'm willing to try whatever to try and fix this problem, I know we should be able to track it down.

Here is another clip in SMB2 that really shows an extreme example of this ghosting effect.
https://clips.twitch.tv/HumbleZealousAr ... WholeWheat

I also have access to a (cheap) oscilloscope for a few days if anyone wants me to take any measurements.

[Quantum]

Here are some pictures of my install: http://imgur.com/a/H6kZX

I've confirmed my SCART cable has no passive components.

I've connected the RGB lines before the coupling capacitors and the effect is drastically reduced. It's not 100% gone but I'd call it acceptable.
Before coupling capacitors: https://www.youtube.com/watch?v=wH9zr6a ... e=youtu.be
After coupling capacitors: https://clips.twitch.tv/HumbleZealousAr ... WholeWheat

viletim, you said that running in this mode will overheat the video encoder -- how do I proceed to make this a permanent fix?

[FBX]

After coupling capacitors: https://clips.twitch.tv/HumbleZealousAr ... WholeWheat

That link loads a white screen.

[Quantum]

After coupling capacitors: https://clips.twitch.tv/HumbleZealousAr ... WholeWheat

That link loads a white screen.

It works for me, check your adblockers/script blockers.

Here's a snip:


Edit: also hi FBX! Love your palettes, using your palettes on my NESRGB right now

Edit2: Also had the sampling phase on my OSSC not quite right which is why the edges are kind of fuzzy on the twitch clip. This doesn't affect the ghosting at all.

[unmaker]

viletim, you said that running in this mode will overheat the video encoder -- how do I proceed to make this a permanent fix?

Probably by replacing the coupling caps with new ones.

Would you be able to provide screens of SMB? I'm curious if the noise you're seeing is similar to mine.

[FBX]

It works for me, check your adblockers/script blockers.

It's working now. Twitch must have been down at the time I clicked on it. I even waited a few mins to try again and it was still down. Works fine now though.

Edit: also hi FBX! Love your palettes, using your palettes on my NESRGB right now

Thanks! I'm actually very interested in giving nakedarthur's finalized palette a try once Tim makes a firmware with it. I think it compliments my NTSC Hardware palette quite nicely as a toggle switch alternative, just from what I've seen of it in emulators.

[Quantum]

viletim, you said that running in this mode will overheat the video encoder -- how do I proceed to make this a permanent fix?

Probably by replacing the coupling caps with new ones.

I'm kind of irritated that they'd need replacing, as the board is new

viletim, can you let me know if this is the appropriate next step? What size and rating are the caps? I think I have some 22 uF caps in that footprint.

Would you be able to provide screens of SMB? I'm curious if the noise you're seeing is similar to mine.

I might hook up my RGB lines after the caps tonight then I'll take some screens.

[unmaker]

Would you be able to provide screens of SMB? I'm curious if the noise you're seeing is similar to mine.

I might hook up my RGB lines after the caps tonight then I'll take some screens.

Actually no need. I soldered the lines before the coupling caps and it made no difference for me. So I'm sure my issue is different than yours.

[Uzumaki]

I don't know how the formulas are calculated, so maybe you could help me out on this:

Earlier you stated:

1/(1/470 + 1/91) = 76.2 = close enough to 75 ohm output impedance.

So what I'm asking since I'm not an electrical engineer is the logical progression:

If 1/(1/470 + 1/91) = 76.2 (J8 closed)

1/(1/470) = ?? (as in J8 is open)

1/(1/680) = ?? (my NESRGB12)

And again my apologies for not having a clue here, but the above is what I'm trying to figure out.

-FBX

I too am confused by this. Is it safe to use the composite sync from NESRGB that has no J8 jumper with a framemeister? Or should we be using composite video sync? My scart sync cable has no components in it, just straight pass through.

[FBX]

I don't know how the formulas are calculated, so maybe you could help me out on this:

Earlier you stated:

1/(1/470 + 1/91) = 76.2 = close enough to 75 ohm output impedance.

So what I'm asking since I'm not an electrical engineer is the logical progression:

If 1/(1/470 + 1/91) = 76.2 (J8 closed)

1/(1/470) = ?? (as in J8 is open)

1/(1/680) = ?? (my NESRGB12)

And again my apologies for not having a clue here, but the above is what I'm trying to figure out.

-FBX

I too am confused by this. Is it safe to use the composite sync from NESRGB that has no J8 jumper with a framemeister? Or should we be using composite video sync? My scart sync cable has no components in it, just straight pass through.

Yeah I don't understand why nobody can explain this to us. It's like some sort of forbidden knowledge, when all I want to know is what the final impedance value is on scenario 2 and 3. We got as far as J8 closed equaling a final value of 76.2 Ohms, meaning you don't need components on your sync line to attenuate this signal. But I still need to know what comes out of the line with J8 open and also what comes out of the line for NESRGB12. Why can't we get a straight answer?

I was telling a friend the other day, if I were and electrical engineer, I wouldn't hesitate to help people out with this and give a clear cut explanation, knowing what it's like to be on the other side of this knowledge. I guess that's just me being weird though.

-FBX

[Ripthorn]

I don't know how the formulas are calculated, so maybe you could help me out on this:

Earlier you stated:

1/(1/470 + 1/91) = 76.2 = close enough to 75 ohm output impedance.

So what I'm asking since I'm not an electrical engineer is the logical progression:

If 1/(1/470 + 1/91) = 76.2 (J8 closed)

1/(1/470) = ?? (as in J8 is open)

1/(1/680) = ?? (my NESRGB12)

And again my apologies for not having a clue here, but the above is what I'm trying to figure out.

-FBX

I too am confused by this. Is it safe to use the composite sync from NESRGB that has no J8 jumper with a framemeister? Or should we be using composite video sync? My scart sync cable has no components in it, just straight pass through.

Not safe at all...

Spoiler

[FBX]

My scart sync cable has no components in it, just straight pass through.

Not safe at all...

I remember that post in the Framemeister thread. Something about power surge through the RGB lines? A good case for having caps in the lines?

[Ripthorn]

My scart sync cable has no components in it, just straight pass through.

Not safe at all...

I remember that post in the Framemeister thread. Something about power surge through the RGB lines? A good case for having caps in the lines?

Well, power surge was just a speculation, but since my scart cables from both my AV Fami and SNES does not have any resistor on csync line, I'm pretty sure that's what caused the problem. Almost burned an expensive component, I believe it was the CPLD.

[FBX]

Well, power surge was just a speculation, but since my scart cables from both my AV Fami and SNES does not have any resistor on csync line, I'm pretty sure that's what caused the problem. Almost burned an expensive component, I believe it was the CPLD.

It's hard to believe TTL sync would cause that kind of visible physical damage. That definitely looks like something far more severe. I suppose I could be wrong though.

[Ikaruga11]

Any advantages of a Top Loader NES for RGB?

[Quantum]

Any advantages of a Top Loader NES for RGB?

I think if you use a multi-av port you can do the mod without cutting the case which is a big deal to a lot of people.

[Ikaruga11]

Any advantages of a Top Loader NES for RGB?

I think if you use a multi-av port you can do the mod without cutting the case which is a big deal to a lot of people.

Yeah, that is pretty tempting.

[viletim]

Quantum,

The capacitors need to be replaced. Perhaps just one or two, but it's easy enough to replace all five. They are tantalum capacitors 220u, 6.3v, 3528 metric size. I'll send you some replacements if you like (email me) otherwise you can buy from Digikey 478-8166-1-ND or Farnell 2688582. To remove the old capacitor just heat up the solder joint on one end with the iron, add a little bit of solder, then lift up that side of the component with tweezers. Then heat up the other side and remove from the board.

[viletim]

I too am confused by this. Is it safe to use the composite sync from NESRGB that has no J8 jumper with a framemeister? Or should we be using composite video sync? My scart sync cable has no components in it, just straight pass through.

It is safe to directly connect the CS# or any signal containing sync to a Framemeister, SCART or RGB21 television, or any other TV/monitor/scaler that expects composite video as sync. This is true for all versions of NESRGB and in fact any of my other products that output RGB video. There is never a need to connect components to the video/sync signals in the video cable for my products.

Yeah I don't understand why nobody can explain this to us. It's like some sort of forbidden knowledge, when all I want to know is what the final impedance value is on scenario 2 and 3. We got as far as J8 closed equaling a final value of 76.2 Ohms, meaning you don't need components on your sync line to attenuate this signal. But I still need to know what comes out of the line with J8 open and also what comes out of the line for NESRGB12. Why can't we get a straight answer?

I was telling a friend the other day, if I were and electrical engineer, I wouldn't hesitate to help people out with this and give a clear cut explanation, knowing what it's like to be on the other side of this knowledge. I guess that's just me being weird though. :-P

Impedance is only one parameter of the output. It's not enough information by itself to be useful.

A composite video input has a input impedance of 75 ohms. It expects the sync part to have an amplitude of 0.3 Vpp (peak to peak).

NESRGB12 has a 680 ohm series on the CS# signal on the board. If you connect it directly to a composite input you get a signal which is about 0.5 Vpp. The later version of hardware NESRGB14 you will get a signal of about 0.7 Vpp if you directly connect CS#. It's larger than usual, but should work without any problem. It will definitely not damage anything.

[FBX]

A composite video input has a input impedance of 75 ohms. It expects the sync part to have an amplitude of 0.3 Vpp (peak to peak).

NESRGB12 has a 680 ohm series on the CS# signal on the board. If you connect it directly to a composite input you get a signal which is about 0.5 Vpp. The later version of hardware NESRGB14 you will get a signal of about 0.7 Vpp if you directly connect CS#. It's larger than usual, but should work without any problem. It will definitely not damage anything.

Ah now we're getting somewhere! I recall in Voultar's video, the acceptable range is anywhere between 0.9 and 0.1 Vpp (I'm of course rounding off and paraphrasing here). So what this means neither version of these NESRGB boards need resistors in the csync lines of RGB cables, correct? So in my case, the SNES RGB cable would technically not be accurate to use because it does have a resistor in the csync line (somewhere around 420 Ohm I think it was).

Lastly, what would the Vpp be with J8 open on the line?

[Quantum]

Quantum,

The capacitors need to be replaced. Perhaps just one or two, but it's easy enough to replace all five. They are tantalum capacitors 220u, 6.3v, 3528 metric size. I'll send you some replacements if you like (email me) otherwise you can buy from Digikey 478-8166-1-ND or Farnell 2688582. To remove the old capacitor just heat up the solder joint on one end with the iron, add a little bit of solder, then lift up that side of the component with tweezers. Then heat up the other side and remove from the board.

I'll grab some off digikey, thanks.

[Uzumaki]

I too am confused by this. Is it safe to use the composite sync from NESRGB that has no J8 jumper with a framemeister? Or should we be using composite video sync? My scart sync cable has no components in it, just straight pass through.

It is safe to directly connect the CS# or any signal containing sync to a Framemeister, SCART or RGB21 television, or any other TV/monitor/scaler that expects composite video as sync. This is true for all versions of NESRGB and in fact any of my other products that output RGB video. There is never a need to connect components to the video/sync signals in the video cable for my products.

Yeah I don't understand why nobody can explain this to us. It's like some sort of forbidden knowledge, when all I want to know is what the final impedance value is on scenario 2 and 3. We got as far as J8 closed equaling a final value of 76.2 Ohms, meaning you don't need components on your sync line to attenuate this signal. But I still need to know what comes out of the line with J8 open and also what comes out of the line for NESRGB12. Why can't we get a straight answer?

I was telling a friend the other day, if I were and electrical engineer, I wouldn't hesitate to help people out with this and give a clear cut explanation, knowing what it's like to be on the other side of this knowledge. I guess that's just me being weird though.

Impedance is only one parameter of the output. It's not enough information by itself to be useful.

A composite video input has a input impedance of 75 ohms. It expects the sync part to have an amplitude of 0.3 Vpp (peak to peak).

NESRGB12 has a 680 ohm series on the CS# signal on the board. If you connect it directly to a composite input you get a signal which is about 0.5 Vpp. The later version of hardware NESRGB14 you will get a signal of about 0.7 Vpp if you directly connect CS#. It's larger than usual, but should work without any problem. It will definitely not damage anything.

Thank you for clearing this up, Tim. I think our confusion came from the documentation which states by default: NESRGB CS# outputs TTL sync. In our experience with consoles like the genesis and SNES this logic level sync is between 3-5 Volts (if I'm not mistaken) and requires resistors on the cable.

[Quantum]

Quantum,

The capacitors need to be replaced. Perhaps just one or two, but it's easy enough to replace all five. They are tantalum capacitors 220u, 6.3v, 3528 metric size. I'll send you some replacements if you like (email me) otherwise you can buy from Digikey 478-8166-1-ND or Farnell 2688582. To remove the old capacitor just heat up the solder joint on one end with the iron, add a little bit of solder, then lift up that side of the component with tweezers. Then heat up the other side and remove from the board.

I've replaced the capacitors and everything looks as if the signals were hooked up directly to the encoder. It's still there but you have to squint reeeeeeeeeeal hard.

All in all, it's a huge improvement and I'm satistfied. Thanks tim, I'm a big fan of your boards.

[Ripthorn]

I have a question regarding the original composite video:

Does the original composite video still works with the NESRGB installed or I have to use the PPUV pin and turn off the board trough a four position palette switch?

[Guspaz]

You have two options to get composite video when an NESRGB is installed:

1) Turn off the NESRGB using a four position switch (or a three-position that you set one of the positions to be off), after which the original NES composite output is usable
2) Use the NESRGB composite video output, which is higher quality than the original NES composite video anyhow.

Alternatively, I guess you could cut the trace to the NES composite video output and route the NESRGB composite output through the original composite output port? I don't know how well that would work.

[Ripthorn]

You have two options to get composite video when an NESRGB is installed:

1) Turn off the NESRGB using a four position switch (or a three-position that you set one of the positions to be off), after which the original NES composite output is usable
2) Use the NESRGB composite video output, which is higher quality than the original NES composite video anyhow.

Alternatively, I guess you could cut the trace to the NES composite video output and route the NESRGB composite output through the original composite output port? I don't know how well that would work.

Yeah... I know these options
I'm not interested on composite video from NESRGB because is converted from RGB, I just wanted to see the original blue sky from Super Mario Bros.
I'll use the IGR board, probably it would be too messy with an option to turn off.

[Quantum]

Alternatively, I guess you could cut the trace to the NES composite video output and route the NESRGB composite output through the original composite output port? I don't know how well that would work.

This is kind of what I did. I actually clipped the small wire at the RF port and brought a wire from the PPUV pad to the RF out.

[leonk]

Alternatively, I guess you could cut the trace to the NES composite video output and route the NESRGB composite output through the original composite output port? I don't know how well that would work.

This is kind of what I did. I actually clipped the small wire at the RF port and brought a wire from the PPUV pad to the RF out.

I'm wondering if there are any adverse effects in doing this. If you use a Nintendo multiAV port, you'll have composite video output pin there + composite video feeding to the RF block.

[Quantum]

Alternatively, I guess you could cut the trace to the NES composite video output and route the NESRGB composite output through the original composite output port? I don't know how well that would work.

This is kind of what I did. I actually clipped the small wire at the RF port and brought a wire from the PPUV pad to the RF out.

I'm wondering if there are any adverse effects in doing this. If you use a Nintendo multiAV port, you'll have composite video output pin there + composite video feeding to the RF block.

There's no composite video feeding back into the RF block, the connection between the RCA jack and the RF block is snipped. I don't have a multiAV port either.

[mikejmoffitt]

Alternatively, I guess you could cut the trace to the NES composite video output and route the NESRGB composite output through the original composite output port? I don't know how well that would work.

This is what I did on my NES.