Hyper64 Video interference "fixed"

skate323k137

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Mainly posting this as documentation in case someone has this problem in the future and ends up scratching their heads like I was.

I recently grabbed a couple of rev1 hyper64 mobos (one of which is on its way to Panda island to live amongst the pulstars). Lucky for me they came with the extra 4 pin looms for stereo sound and power support, and a pair of samurai shodown 64 carts.

I get everything hooked up to my supergun/PVM, and there's wavy interference over the picture. Picture itself is OK, but diagonal ghosty-looking lines are "rolling" across the picture.

I think, OK, maybe this is drawing a lot of power, and the supergun I'm using has the video lines running close to the (unshileded) power lines. I'll split those up. So I take the time to rebundle the wires coming from my JAMMA connector and isolate the power from the video wires. No dice; same bullshit interference in the video :/

Around this time I start googling. I find a couple threads where people bridged logic ground and earth ground on the power supply to "fix" similar issues. To me that didn't sound like a very good idea, but it inspried a little more tinkering. I pull out my volt meter, set it to ohms, and probe the jamma ground pins and the metal case of the hyper64 mobo. Bingo... continuity! Still not wanting to bridge the DC ground and AC ground (signal and earth ground) at the PSU itself, I decided I'd just earth ground the metal casing of the hyper64 motherboard. I'll be damned if that didn't fix it; video is perfect.

This -may- be more of an issue with the PSU itself (HAPP power pro), as I've found other cases of that being the case. This same supergun has similar interference with CPS2 boards, but not -nearly- as bad as it was with the hyper64. It really hasn't bothered me at all with other boards. Down the road I may try a different brand of PSU, as my other supergun uses a "meanwell" PSU and never had problems like this with CPS2 (or any other) boards.

TL;DR, I earth grounded the metal case of my hyper64 mobo and it fixed my video problems.
 
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Kid Panda

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This is interesting. I would think the extra power with extra ground cables would have fixed this issue. Good to know it was an easy fix :D
 

skate323k137

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Super necro bump, I've found this to be an issue with the happ power pro PSU's. Connecting the DC ground to the AC (earth) ground seems to clear it right up.

On the MeanWell PSU's that I use that never gave me this problem, the dc ground / COM seems to already be connected to earth ground internally according to my multimeter.
 

Kid Panda

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Super necro bump, I've found this to be an issue with the happ power pro PSU's. Connecting the DC ground to the AC (earth) ground seems to clear it right up.

On the MeanWell PSU's that I use that never gave me this problem, the dc ground / COM seems to already be connected to earth ground internally according to my multimeter.


Oh man, when I dropped a switching power supply in the AWSD, I was getting crazy interference till I did what you ended up doing. So odd, glad you got it cleared up!
 

madman

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Somewhat necro bump, was getting pretty bad interference on my SG w/my Happ Power Pro and found this thread. Significant improvement after doing this, I'll dig up some thicker gauge wire tomorrow and re-do it. Kind of bummed something like a Happ product would have this issue. My PGM now looks flawless, Brezza Crystal board as well, Atomiswave not quite perfect yet but much better.
 

Xian Xi

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Somewhat necro bump, was getting pretty bad interference on my SG w/my Happ Power Pro and found this thread. Significant improvement after doing this, I'll dig up some thicker gauge wire tomorrow and re-do it. Kind of bummed something like a Happ product would have this issue. My PGM now looks flawless, Brezza Crystal board as well, Atomiswave not quite perfect yet but much better.

Its a common issue with superguns. "Builders" don't do a lot of things they should.
 

skate323k137

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Its a common issue with superguns. "Builders" don't do a lot of things they should.

This is definiely an issue with the happ psu more than the supergun. When I was troubleshooting this I tried everything... Individually shielded video wires included. Nothing cleared it up except bridging DC gnd and earth gnd, or swapping to a different PSU.
 

Xian Xi

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This is definiely an issue with the happ psu more than the supergun. When I was troubleshooting this I tried everything... Individually shielded video wires included. Nothing cleared it up except bridging DC gnd and earth gnd, or swapping to a different PSU.

No it's the supergun(product), any real builder would know to bridge them. None of mine do that because I do exactly that.
 

skate323k137

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No it's the supergun(product), any real builder would know to bridge them. None of mine do that because I do exactly that.

At this point we're talking about 6 of one, half a dozen of the other. I know your stuff is top notch, so it's good you handle this, but some quality power supplies handle it for you already. Theoretically if the power supply weren't causing the problem to begin with, you wouldn't have to know to fix it (or there'd be nothing to fix).
 

madman

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At this point we're talking about 6 of one, half a dozen of the other. I know your stuff is top notch, so it's good you handle this, but some quality power supplies handle it for you already. Theoretically if the power supply weren't causing the problem to begin with, you wouldn't have to know to fix it (or there'd be nothing to fix).

Or in the case of a HAS Supergun where one provides their own power supply.
 

Xian Xi

JammaNationX,
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At this point we're talking about 6 of one, half a dozen of the other. I know your stuff is top notch, so it's good you handle this, but some quality power supplies handle it for you already. Theoretically if the power supply weren't causing the problem to begin with, you wouldn't have to know to fix it (or there'd be nothing to fix).

Every supergun I have repaired has always had this problem no matter what power supply it is. I know where you are coming from though.
 
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