SNES Diagonal Line Interference?

[mugenmidget]

With the release of the Neo Myth SNES flash cartridge, I noticed a peculiar issue upon first using it.  There were faint diagonal interference lines visible in the menu of this cartridge, especially when it was flashing ROMs.  The fact that the interference increases when it was flashing made me wonder if it was a power issue.  In game, the interference isn't usually noticeable but it pops up every now and then (especially on blue backgrounds).

I decided I would try some real SNES games and see if I could detect the same interference.  It was a lot harder to find, but it was definitely there.  I only have third party S-Video cables, so I thought I'd try the official composite cables and see if the interference showed up.  Sure enough, it's still there.  To further rule things out, I tried swapping power supplies, and still saw the interference patterns.

I'm wondering if the SNES is  damaged at this point, because I don't necessarily remember this interference but I never really had a TV good enough to spot it.  Is it normal for SNES systems to display this kind of interference?  If it's damaged, could third party S-Video cables be responsible?  The Neo hardware may have also played a part if it is drawing more power, but I really wouldn't know.

The interference shows itself on every TV I've tried so far, so it doesn't seem to be display related.  The console (or at least the AV port) seems to be at fault.  I'll see if I can get another system to try things out on.

Anyways, here are some videos of the problem in question, maybe someone will be familiar with it:

The Neo cartridge with Killer Instinct flashed (look for the faint diagonal lines running across the purple background): http://s207.photobucket.com/albums/bb255/mugenmidget/?action=view&current=neomythki.flv

The genuine KI cartridge (interference is much fainter, but it's there in the same places): http://s207.photobucket.com/albums/bb255/mugenmidget/?action=view&current=realki.flv

And here's a still image of the interference captured by the Gamebridge:



Just curious if anyone is familiar with such a thing happening, I'll try to report back if I get another system to look at.  Thank you and let me know if you have any other suggestions for things I should try.

[Ocelot85]

Maybe there is something creating interference nearby other than the TV or console, try moving them to another room perhaps. You could also try disconnecting all the connections to your TV other than the console, unless you already have.

[mugenmidget]

Hm, yes things should be fairly isolated as I was trying it in different rooms.  But I'll continue to mess with it later and see if I can get any results.  I'll also need to get my hands on some more systems and see what happens with those.

[Endymion]

That really does look like simple RF interference. Mechanical electric motors can cause this, fans, a/c unit, refrigerator, etc. Are you using a surge protector? Keep everything on the same mains as well.

[mugenmidget]

I've tried multiple surge protectors, power strips, and sometimes completely without but haven't seen improvement.   I might have to bring the equipment over to someone else's place and try it there to completely isolate any chance of interference.

[viletim]

With the release of the Neo Myth SNES flash cartridge, I noticed a peculiar issue upon first using it.  There were faint diagonal interference lines visible in the menu of this cartridge, especially when it was flashing ROMs.  The fact that the interference increases when it was flashing made me wonder if it was a power issue.  In game, the interference isn't usually noticeable but it pops up every now and then (especially on blue backgrounds).

I'd point towards the power supply, flash roms do draw more power when they're being programmed. Not necessarily the AC adapter itself though...

[mugenmidget]

Hm, then I may have to find a model that doesn't exhibit these problems and then keep the Neo Myth out of it and see if it stays clear.  Thank you everyone for all the help so far, I hope I can find some more SNES systems to test things further.