Megadrive 1 VA1 revision Jailbars even after RGB bypass

[DanMAk]

I have a Japanese Mega Drive 1 with VA1 motherboard that had a lot of jailbars. I decided to do the RGB bypass using a good RGB board (ArcadeTV), I took care to perform accurate soldering and use insulated wires connected to the VDP legs, I also cut the tracks between the encoder to minimaze interference. Even after all this work my Mega Drive 1 still shows jailbars. It improved about 80%, they were very evident jailbars and after the RGB bypass they were very light and only appear in light and dead colors, mainly light shades of gray. It became much more discreet and they are not noticed in most games, except games that use a lot of gray tones like World of Illusion, in this game it’s impossible not to notice the Jailbars and I’m wondering if there’s anything else I can do about it because it’s really annoying to live with this problem. Below have link with pictures showing the Jailbars in the game and my installation of RGB Bypass.
Is there anything else I can do to eliminate jailbars or should I just live with it on my Mega Drive?

https://photos.app.goo.gl/WtQX7ZjumBNRwRTd8
https://photos.app.goo.gl/jb5xE3dpdKPki6BJA
https://photos.app.goo.gl/4bqesV93brAKchPp7
https://photos.app.goo.gl/mbH5PyMfPFhXKhzG7
https://photos.app.goo.gl/8iZ3oojjaTLoBSgz5

Note: The strange thing is that I have another Japanese Mega Drive 1 also with a VA1 motherboard that I installed exactly the same RGB bypass board (ArcadeTV) and which has Jailbars practically unnoticed after RGB bypass. I also have a Mega Drive 2 VA4 that I installed Triple Bypass and this one is 100% free of any Jailbar signs, being the perfect console.

[BuckoA51]

NEVER solder direct to the VDP legs, this will likely kill the VDP over time.

[DanMAk]

I had done from the tracks of VDP before but the Jailbar effect got worse. Soldering on the legs of the VDP is one of the best ways to avoid interference from motherboard and it’s okay to do if you recreate The three 5.6k pull-up resistor circuit like I did. All this is documented in the links:

https://www.retroorgb.com/genesisrgbbypass.html
https://www.retroorgb.com/fix-for-all-rgb-bypassed-sega-genesis.html

The point is that even I know I already done, I cut the RGB and Sync tracks that come out of the encoder to avoid interference too but my megadrive still has a number of jailbars in gray colors. I have another Japanese mega drive 1 also with the same VA1 motherboard and exactly the same RGB work which is almost perfect with very very minimal Jailbars. I don’t understand why this particular mega drive is not jailbar-free. I would like to know if anyone else has any ideas for me to further reduce this plague of Jailbars because everything I know I’ve already done. I read something about regulating the memory clock but I don’t know exactly what it is. I would like to know if anyone else has any ideas.

[BuckoA51]

If you do lift the legs and solder direct then you must add 5k6 and 2k2 pull ups on the bypass board… but still you now have a length of wire which has minimal resistance but nevertheless is stressing the VDP, so we strongly advise against it.

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