Rgb interference question

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alfredocalza
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Rgb interference question

Post by alfredocalza »

Hi! I am currently performing 2 nesrgb mods; one or a European front loader and another one for a US top loader. I am pretty advanced in the process for both consoles, the only thing left to do is hook up all the wires from the nesrgb boards to the scart out connectors.

I wanted to minimize interference as much as I could and have the best possible video output, so I was planning on using shielded cables for the audio and sync lines, but I wonder if I should also use shielded cables for the rgb lines? The cables that I am talking about are the ones that go from the nesrgb boards to the scart out connectors (scart out is in my case; most people use snes multi out connectors instead)
alfredocalza
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Re: Rgb interference question

Post by alfredocalza »

In other words, can RGB video signals crosstalk with each other?
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TmEE
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Re: Rgb interference question

Post by TmEE »

Yes, they can. It will not hurt to use shielded cabling to the connector (or very least twisted pairs) but it is all moot when you have a cheap SCART cable that doesn't shield anything.
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Ben Boldt
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Re: Rgb interference question

Post by Ben Boldt »

I have taken cheap SCART cables, replaced the wiring with a VGA cable with its ends chopped off, keeping the ferrite beads in place. That works really great, it is a very big difference. I have made SNES/N64 and Genesis cables this way.
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TmEE
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Re: Rgb interference question

Post by TmEE »

That is how I have made a few really good cables too, though not every cable will do, some use steel wires and are unsolderable due to it...
alfredocalza
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Re: Rgb interference question

Post by alfredocalza »

Great! Thank you all! I have a 24 awg copper shielded cable that I think I can use. All of my Scart cables are premium quality and super thick and heavy with individual shielding. I got them NOS from an ebay seller when I lived in Europe.
alfredocalza
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Re: Rgb interference question

Post by alfredocalza »

Question: Do I need to add 220uf capacitors to the rgb lines? My cables are normal rgb cables without any capacitors in them. I already did the installation, and it worked with my ossc without the capacitors, but I am afraid that I might damage something in the long term.. Here are some pictures of the mod:
20220408_231358.jpg
20220408_231314.jpg
20220408_223551.jpg
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TmEE
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Re: Rgb interference question

Post by TmEE »

No, the board already has all necessary things installed, only straight wires cable is necessary.
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Ben Boldt
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Re: Rgb interference question

Post by Ben Boldt »

I have to say, The SCART connector out the back looks really good. There are a lot of ugly ways that people get RGB out of their NES and yours is pretty in my opinion. And sturdy. Clever placement of the switch. Your cable routing is great inside too, nice job.

It looks like you replaced your ZIF connector with something different too? Do you mind sharing what that thing is/does? How is it secured? it looks like shoving in a cartridge too hard would want to disconnect it from the motherboard; what prevents that? It seems like a great spot to add ESD protection and 3.3V pirate cart support/protection.
alfredocalza
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Re: Rgb interference question

Post by alfredocalza »

Ben Boldt wrote: Sun Apr 17, 2022 12:17 pm I have to say, The SCART connector out the back looks really good. There are a lot of ugly ways that people get RGB out of their NES and yours is pretty in my opinion. And sturdy. Clever placement of the switch. Your cable routing is great inside too, nice job.

It looks like you replaced your ZIF connector with something different too? Do you mind sharing what that thing is/does? How is it secured? it looks like shoving in a cartridge too hard would want to disconnect it from the motherboard; what prevents that? It seems like a great spot to add ESD protection and 3.3V pirate cart support/protection.
Thanks! I spent literally hours figuring out the best placements and routes. I was able to keep all the shields with minor cuts. The connector is a blinking light win connector that I had from another console that broke down; hence I had to do this one. I bought that connector back in 2018, but I think that they are no longer available.
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