Reply To: Koryuu s-video interference

[Noctua]

Okay, I haven’t shared any information in a while. It has been quite busy, so my apologies for that.

Anyway.
I strongly believe I now understand where the interference or “dot crawl” is coming from. I think it has to do with the comb filter of the Koryuu. Testing multiple configurations with different equipment, this is the conclusion that I keep returning to.

* Using High quility shielded S-Video cables from RetroAccess (both original and modified for PAL N64)
* Using multiple revisions of the console
* Using different settings on the OSSC
All result in a noisy image

* Using a Framemeister, Retrotink 2x Pro, Retrotink 2x Pro to OSSC (VGA)
All result in considerable less, but still somewhat noticeable dot crawl. Maybe because the Koryuu has a sharper image/signal?

The “a-ha” moment came as soon as I used the new Retrotink MINI. This device has two options for its comb filter. Auto and Retro. The website states that this device has been built in such a way that it supports N64 PAL consoles over s-video (both normal and PAL modified s-video cables seem to result in the same image). Also saying that if there is any dot crawl present in the image that you should switch to the “auto” comb filter. This proved wonders. The image with this device + s-video with the “auto” comb filter, is the cleanest I’ve ever seen my unmodified PAL N64.

However, due to what the Koryuu is, I believe that with an adjusted comb filter for this device it can look even better than the Retrotink Mini. Especially when connected to the OSSC. Is it possible for the developer to look into this comb filter issue and change it with a firmware revision?