Jailbars / vertical banding question

[rednakes1]

Any idea what causes these jailbars on this Colecovision with a revision H2 motherboard?  They are extremely noticeable on bright coloured backgrounds like the skill select screen or the green shown below.

 

I tried replacing capacitor C106 but that did not make a difference.  A second Colecovision does not have this problem on same TV.

 

This is happening on the RF but I’m guessing the problem will still show up with an AV mod.

 

Edited July 13 by rednakes1

[+-^CrossBow^-]

On 7/13/2024 at 12:11 PM, rednakes1 said:

Any idea what causes these jailbars on this Colecovision with a revision H2 motherboard?  They are extremely noticeable on bright coloured backgrounds like the skill select screen or the green shown below.

 

I tried replacing capacitor C106 but that did not make a difference.  A second Colecovision does not have this problem on same TV.

 

This is happening on the RF but I’m guessing the problem will still show up with an AV mod.

 

Far as I know many revisions of the CV produce these jail bars. The retrotink 5x pro even has a setting that can be adjusted to blur and blend them in to compensate as they can be present on not just RF and composite as you have seen, but also show up a little with the RGB upgrade in place. I think I read or saw where it seems the source for them is the VDP itself but I'm sure there is more to it than that. I believe the only real way to get a perfect image from the CV is to get an F18A as it replaces the VDP and video RAM completely.

 

@Ruggers Customs has also stated in other places that I think the Rev C of the Colecovision is the best revision for the cleanest composite output from the console? I also have an H2 rev and it has the same vertical bars and pretty crappy composite output as well, but still better than the snow blizzard field I was getting from the RF originally.

 

[rednakes1]

19 minutes ago, -^CrossBow^- said:

Far as I know many revisions of the CV produce these jail bars. The retrotink 5x pro even has a setting that can be adjusted to blur and blend them in to compensate as they can be present on not just RF and composite as you have seen, but also show up a little with the RGB upgrade in place. I think I read or saw where it seems the source for them is the VDP itself but I'm sure there is more to it than that. I believe the only real way to get a perfect image from the CV is to get an F18A as it replaces the VDP and video RAM completely.

 

@Ruggers Customs has also stated in other places that I think the Rev C of the Colecovision is the best revision for the cleanest composite output from the console? I also have an H2 rev and it has the same vertical bars and pretty crappy composite output as well, but still better than the snow blizzard field I was getting from the RF originally.

 

Yes this H2 has a bad blizzard effect on the RF, so a composite mod will be an improvement.

 

BTW I tried my Rev J Colecovision on the RF and it happened to show the jailbars too.. I actually didn’t notice this before. But its RF in general is very good..  With its composite output I don’t see any jailbar.

Edited July 15 by rednakes1