7800 Video Mods

[Tempest]

This weekend I managed to pick up a 7800.  This is the first 7800 I've owned in several years since selling off my original one.  It's an early A1 revision so it has the expansion port still.

 

I want to get it S-Video modded, but I've been out of the loop for years on this.  What's the latest and greatest S-Video mod out there?  The last time I had one I had a Longhorn Engineer mod in it and it worked fine but I think there are different ones now.

[Trebor]

Bryan's UAV appears to be top of the list.  Magic Knight is another option and works very well too.

 

Though, the 7800 really needs a RGB mod like the 2600 and NES have received.   RGB mods completely alleviate the color palette issues between CRT and HD flat panels, as the color values are hard coded and can be customized.  This issue is best seen under the 7800 with Commando.

 

Hoping someday, if not Tim Worthington, someone else takes up the challenge.

[Tempest]

I'll have to check the UAV mod out.  I'm using this on a CRT so it shouldn't be an issue.

[Tempest]

So who sells the UAV for the 7800 and does anyone do installs?  This is way beyond my skills.

[+DrVenkman]

13 minutes ago, Tempest said:

So who sells the UAV for the 7800 and does anyone do installs?  This is way beyond my skills.

@MacRorie sells the UAV these days and I believe @-^Cro§Bow^- does installations. 
 

I have one (installed myself) and I’m quite pleased.

 

As for RGB, I know folks on the other side of the world rave but in North America it’s really a non-starter for most people. 

[+-^CrossBow^-]

@DrVenkman I appreciate the mention, Thanks!

 

@Tempest

Yeah I offer installs for these. I actually have one basic UAV and several of Magic Knights boards on hand currently plus the required RCAs..etc. Shoot me a PM if you want more details.

 

Edited September 16, 2019 by -^Cro§Bow^-

[Trebor]

1 hour ago, DrVenkman said:

...As for RGB, I know folks on the other side of the world rave but in North America it’s really a non-starter for most people. 

An available RGB video output is not important.  It can be S-Video and/or Composite.  The aforementioned ones by Tim provide RGB, S-Video and Composite outputs.  It is this function of the RGB Mod that is of most interest though (Modified verbiage to fit the 7800):

 

"It works in a similar manner to my NESRGB board. That is, it sits between the CPU and MARIA (the name of the 7800 graphics chip) and stores the data which is meant to be written to the MARIA palette registers.  MARIA is fed with dummy colors instead. The various luma outputs from the MARIA, in addition to the color data stored, is then used to create a RGB version of the original video signal. Essentially, the board creates the RGB video signal by bypassing the color generation logic in the MARIA. The video timing is unchanged."

 

It allows the 'perfect' palette for each console/user.  The 2600 version stores six different color palettes to choose from (Three NTSC and three PAL), and the NES has three.  Palettes can be modified by the user.

 

Feeding that generated RGB video signal to S-Video or/and Composite outputs for the console would be ideal.  Actually, ideal would probably be including HDMI too...lol.

[+DrVenkman]

23 minutes ago, -^Cro§Bow^- said:

@DrVenkman I appreciate the mention, Thanks!

Considering I used your (excellent!) illustrated installation guide to do my own, I thought it worth making the referral.  

[Tempest]

PM Sent.

[ApolloBoy]

12 hours ago, Trebor said:

Bryan's UAV appears to be top of the list.  Magic Knight is another option and works very well too.

 

Though, the 7800 really needs a RGB mod like the 2600 and NES have received.   RGB mods completely alleviate the color palette issues between CRT and HD flat panels, as the color values are hard coded and can be customized.  This issue is best seen under the 7800 with Commando.

 

Hoping someday, if not Tim Worthington, someone else takes up the challenge.

Tim was working on one, but the last time I checked in with him about that was two years ago and I'm not sure if he took it up again or if it's still on the backburner. I'd think it would be more complex than the 2600RGB since you'd have both the MARIA and TIA to contend with.

[+Mitch]

I think the best one I have seen is the old, sadly discontinued, Retrokidz board. I think the UAV board is the second best of what I have seen. I have not tried the Magic Knight board.

My Retrokidz board died at a retro gaming event a few years ago, if anyone want to RE it let me know.

 

Mitch

[juansolo]

19 hours ago, Trebor said:

Bryan's UAV appears to be top of the list.  Magic Knight is another option and works very well too.

 

Though, the 7800 really needs a RGB mod like the 2600 and NES have received.   RGB mods completely alleviate the color palette issues between CRT and HD flat panels, as the color values are hard coded and can be customized.  This issue is best seen under the 7800 with Commando.

 

Hoping someday, if not Tim Worthington, someone else takes up the challenge.

 

It's not so much the colour palette issues, it's the terrible dot-crawl interference you get when running in playing 7800 games on a PAL console. The 2600 is absolutely fine, but the 7800 is easily the worst picture I have coming out of any of my machines. I thought I might have a duffer so bought another and it's exactly the same. They're both s-vid modded one with the MK one with the UAV and they both still do it. We've tried lifting pins and switching things like was done in the past with older mods but to no avail.

We definitely need someone to look into something along the lines of the eTim 2600 RGB or the Sophia 8-Bit RGB mods but for the 7800. I know that the problem is dealing with essentially two separate outputs in the machine though which is why this particular holy grail eludes us still.

Edited September 17, 2019 by juansolo