RGB modded PC Engine issues

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macplusfm
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RGB modded PC Engine issues

Post by macplusfm »

Hi,
I bought an RGB modded coregrafx and have been having problems with it. It's modded with a electronik-repair v2 board and is plugged into a JVC tm-h1950cg thru scart with one of linuxbot3000's input cards. I was using a model 1 genesis adaptor to power it and i believed this was the issue at first, but after changing power adaptors the issue remains. The screen stays in this warped position but is jittering a bit.

Image

I have not set up my turbo everdrive yet but I highly doubt this is whats causing it. I believe it is an issue with sync-on-composite, but i have no idea how to fix the problem. The monitor works fine with a snes sync-on-composite cable, so is something wrong with the sync signal coming from the console? Here is a picture of the board if it helps.

Image

Thanks
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Mobiusstriptech
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Re: RGB modded PC Engine issues

Post by Mobiusstriptech »

Well one thing to be aware of is that board doesn't provide buffered csync. So you are using composite video as sync with it. It could be an issue with your display or the input card not supporting this.
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macplusfm
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Re: RGB modded PC Engine issues

Post by macplusfm »

I find it strange it doesn't work with sync-on-composite because other consoles using it work fine. I've heard of a vcr mode on pvms/bvms to solve this but jvc's don't have a similar setting. Would a sync stripper installed in the scart cable solve this?
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Voultar
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Re: RGB modded PC Engine issues

Post by Voultar »

What a terrible looking clone of one of my older products. It isn't even done correctly...
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macplusfm
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Re: RGB modded PC Engine issues

Post by macplusfm »

Yep, I was pretty disappointed as well, from the small picture i had in the listing assumed it was one of yours due to the red and didn't look any closer. just trying to salvage it as much as i can now
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Syntax
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Re: RGB modded PC Engine issues

Post by Syntax »

Bad ground/loop on the video output?
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Mobiusstriptech
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Re: RGB modded PC Engine issues

Post by Mobiusstriptech »

macplusfm wrote:I find it strange it doesn't work with sync-on-composite because other consoles using it work fine. I've heard of a vcr mode on pvms/bvms to solve this but jvc's don't have a similar setting. Would a sync stripper installed in the scart cable solve this?
You could try it but in all honesty don't use sync strippers. They end up causing more issues. You'd be better off with a switcher like the gscartsw that provides sync regeneration.
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thebigcheese
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Re: RGB modded PC Engine issues

Post by thebigcheese »

Brief look at the linuxbot cards suggests that they take composite as sync and c-sync, which... they should, because sync-on-composite is the standard (for SCART) and c-sync is just that without a video signal. It does seem like a sync issue, though. Composite video doesn't go through that board at all, though, so not sure what's going on there. Install looks clean even if it is a knockoff board, but you may want to think about moving it anyway cuz it's likely to pick up a lot of noise mounted where it is (in my experience). Wouldn't cause sync issues, though. Best guess is check your cable and make sure it doesn't have anything on the sync line. If that checks out, then find a regular composite video cable and make sure that works. If not, you'll need to trace it back and make sure there aren't any issues on the composite line.
fernan1234
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Re: RGB modded PC Engine issues

Post by fernan1234 »

Which version of the Turbo Everdrive are you using, by the way? A while ago last year a bunch of people using variously RGB-modded and unmodded PCEs, including myself, had irresolvable problems using the latest 1.5 version of the Turbo ED. The OS would not be found (showing the message in your first picture), or the OS menu would show corruptions, crash, or be unable to load games.

I had to track down an older 1.4 Turbo ED and all was well.

The distorted image does not look like the one solved by the VCR mode fix. That should just be flagging at the top, but the rest of the picture should look fine, so this is probably something different or additional.
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Syntax
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Re: RGB modded PC Engine issues

Post by Syntax »

Otaku store also sold a heap of SMS scart cables that dont have the sheilding connected on the scart end.

I highly recommend checking the ground from the modboard to the TV.
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macplusfm
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Re: RGB modded PC Engine issues

Post by macplusfm »

Opened up the end of the scart cable and removed a resistor on the sync line, everything looks perfect now aside from usual sync-on-composite artifacts. Thanks to everyone for helping me out
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