NESRGB Interference Issue

[MrMistermister]

Apologies if this question has already been answered (and for being me being quite amateur),

I have an NES frontloader modded with Viletims's NESRGB board and I'm experiencing some odd interference issues that I can't quite track down the source of. The interference manifests itself in horizontal dark lines that move up and down the screen, mostly noticeable in large areas of the same color. I would try to get a picture of it, but all of my attempts of getting a good picture without a capture card have all been for naught.

I've tried removing the capacitors on the RGB lines (since the cable already has them) but that had no effect. Recapping the entire NES also didn't do anything. I've also tried grounding the NESRGB board to one of the screws in the chassis.

My setup consists of, again, a NESRGB modded frontloader (specifically with a Multi-out connector instead of the DIN connector), a retro-access SNES Sync on Luma cable going into a RGB to YPbPr transcoder, and then into a RetroTink 2X. There is also a 47uF capacitor on the 3.3v line (due to my board having one of those fake voltage regulators).

I should mention I didn't notice these issues until I plugged it into the RetroTink 2X through the YPbPr transcoder, but the interference doesn't appear on other consoles like my N64 or PS1 so I'm pretty sure neither the transcoder or the RetroTink 2X are the issue. The interference still manifests in composite and S-Video going into the RetroTink 2X. Got any other suggestions on what I should try?

[Syntax]

Sounds like your getting noise off the 3.3v rail.
You'll need to mod Tims board and use an LDO.

There's a n64 noise thread here that covers this.

[MrMistermister]

Thanks for replying, what LDO would you recommend me buying, and where specifically would I install it on the board? Excuse me for my ignorance as I haven’t worked with regulators really at all.

Speaking of regulators, could replacing the fake regulator with a genuine one possibly be a fix? Tim’s website seems to say that adding the capacitor should be enough.

[viletim]

Speaking of regulators, could replacing the fake regulator with a genuine one possibly be a fix? Tim’s website seems to say that adding the capacitor should be enough.

Your symptom sounds like an unstable regulator. I recommend replacing it. I can send you one if you like. Send me an email for info (orders at etim.net.au).

[MrMistermister]

Awesome. Thank you!

[sofakng]

Speaking of interference, what is the best type of wire to use with the NESRGB?

Is there a type of small shielded wire that could be used to minimize all interference?

[thebigcheese]

Speaking of interference, what is the best type of wire to use with the NESRGB?

Is there a type of small shielded wire that could be used to minimize all interference?

Internally? Doesn't really matter, though I recommend opting for quality wire over crappy wire (ie good copper vs something that doesn't conduct well). For hooking up to a TV, you'll want a fully shielded cable. While I didn't notice much difference in terms of visual interference, if you have video and audio running down the same cable, you'll definitely get some buzz on the audio lines if it's not fully shielded.

[sofakng]

Thanks for the reply. I'm using RetroGamingCables "Pack-A-Punch" which are very large shielded cables but I'm asking about the internal wires from the NES motherboard to the NESRGB.

[thebigcheese]

Thanks for the reply. I'm using RetroGamingCables "Pack-A-Punch" which are very large shielded cables but I'm asking about the internal wires from the NES motherboard to the NESRGB.

If you really wanted to, you could use a shielded multicore cable internally to go from the NESRGB to your output jack, but it would really be overkill and a pain to fit in there. I've done basically just that with the N64RGB and it made no difference in the interference. Assuming that you are not just using bare wire, you aren't going to pick up much (if any) interference with the internal wires. Most of the interference comes from how the signals are routed on the PCBs (traces that are too close to each other) or using cables that aren't fully shielded.

[daskrabs]

Which PSU are you using? Cheap ones cause visible interference. Use an OEM unit for best results.

[MrMistermister]

Good point. Fortunately, I am using an OEM PSU. I even had an extra one lying around and using either one produces the same result.