600XL and Supervideo 2.1 No color or colored shadows

[sskino]

I posted this question on another thread but thought I would make a new post to see if anyone else has had this problem.

 

I recently did the Supervideo 2.1 upgrade to one of my 600XL computers. After all was said and done, I am getting video but it's black and white. No color.

 

Sometimes when I power up the computer I get monochrome with some weird blue and red shadowing (red shadow on the left side, blue shadow on the right side of characters). I've gone through and checked everything but can't find anything obvious.

Has anyone had this problem before?

[Rybags]

Is it PAL or NTSC?

 

I did one of the supervideo upgrades some time back on my 800XL and it made colours more washed out, and RF was practically monochrome. This is on a PAL machine.

 

It's also worthwhile running S-Video rather than composite or RF.

 

There was some corrective action I did to make it a bit better, can't quite remember what.

[+bob1200xl]

The blue and red shadows are the display trying to 'find' the color clock signal. Usually an open circuit in CHROMA. Do you have the right cable plugged into the right input? What kind of monitor are you using and what kind of s-video cable? There are four signals on the Atari video - LUMA, CHROMA, COMPOSITE, and AUDIO. Audio should be easy to test. LUMA gives a b/w image when plugged into the composite input. Composite gives a color image when plugged into the composite input. Chroma give no image when plugged into the composite input.

 

Can you get these sorted out? If you have a composite signal, you can use that as a chroma source.

 

Bob

[sskino]

Thanks for the response!

 

I am using a composite cable which connects to a standard LCD monitor/TV with a video input. I am not using SVIDEO, so coming off the newly installed 5-Pin DIN connector, my video cable is a standard video cable that I use on my 800XL for composite video. And this is an NTSC system.

 

The upgrade states that you should add two resistors on the underside of the PCB which connect the chroma and luma to the appropriate pins of the 5-Pin DIN connector, but while I made these connections, I am only using the standard video out coming off the connector. Should I not have added these two resistors if I was only planning to use composite video out? My monitors do not have S-Video inputs, so I can't really use it anyway, but I figured I may as well connect them in case I wanted to use it at some point down the road.

 

The video output in monochrome is rather clean and looks fairly sharp so at least I know the quality will be good, but I am just trying to figure out why there is no color. I've replaced all of the components that were requested except one resistor (R140) as I cannot seem to locate where this resistor is, but I didn't think this one resistor would make a different between getting color or monochrome. Or is this my problem?

 

 

[_The Doctor__]

I would like a macros or close up photos of the the work you did so far on the top and bottom of the board, that way we can see where and why it might have gone wrong. This way we can see and rule things out. After that is done some answers could be forthcoming.

[sskino]

Thanks. I will get some taken and posted. I was a bit confused by the upgrade document though. In the document, it states that in "Step 1" you should "Desolder and clear all the board holes for the following components:" then it goes on to list several component locations which includes "L12". Well, while it tells you to clear "L12" it makes no mention of installing anything in "L12". Then it goes on to tell you to install a switch at "L13", but it makes no mention of removing the existing component at "L13" in the previous steps, and "L13" has a ferrite coil (or resistor) in place. I tried it with the existing component in place, then I tried it with it removed and a switch in place, and I tried it with a 75 Ohm resistor at L12, which was the only way I could get video at all. L12 is a direct connection to the composite video output on the DIN-5 connection.

 

I will take some pictures and show you what I have done so far and send a copy of the video output. I'm half tempted to try an S-Video to Composite adapter and see if I get color.

[rmzalbar]

I found this thread in a search for help, and although old, I'll post the solution for anyone else who follows my path and ends up here.

 

There is indeed an error in the Super Video 2.1 600XL guide. The switch needs to be wired to the vacated L12 holes, not L13 as indicated in the guide. The inductor already present at L13 should be left alone - if you remove it, you will lose the RF video. Also, R134 is missing from the layout drawing. It's right between R133 and R132, just below the transistor Q8. These changes should fix the missing composite video created by this error.

 

I did not experience any loss of color saturation with Super Video 2.1 on the 600 XL. Video looks excellent on svideo, composite, and RF.

 

I do have an 800XL with poor saturation as an earlier poster mentioned, but it was already poor before I did the SV 2.1. I plan on adding the color saturation boost circuit the 1200XL uses to improve this. Personally I like the saturation boost of the 1200XL. I'll post a guide after I work this out in case anyone else wants the boost on the other XLs.

Edited March 26, 2021 by rmzalbar

[+kheller2]

There seems to be an 800XL error as well (page 9):

Quote

 

December 1993 AC
With all the technical detail of the video hardware articles in our December
issue it was probably inevitable that a few bloopers would sneak in. Fortunately none are catastrophic and are readily obvious to anyone who attempted the hardware hacks. Here's the list of corrections sent in by readers so far:
Page 9, Step 3. Change "R53" to "R52".

Page 23, Step 4. Change "R205" to "R204".

Page 23, Step 5. Change "03" to "02".

 

 

The April 94 issue has what you mentioned for the 600XL:

Quote

ERRATA
A couple pesky typos snuck into the 600XL Super Video upgrade in the December '93 AC, Obviously the work of a bleary-eyed editor staying up way past his bedtime—it's amazing how nuinbes and letters all blur together at 3AM.
Both errors occur on page 10 of the December '93 issue. In the parts list at the top of the right-hand column, change location "L13" to read ''L12". This is where the CV Disable switch is installed. The inductor at location L13 is already in-stalled on the board and should be left in place.
Also, in Figure 8 at the bottom left-hand column, R134 was inadvertently omitted from the drawing. It should be in-serted between R132 and R133 in the board diagram. Our thanks to Decker McAllister of Seal Beach, CA for bringing these items to our Attention. AC regrets any inconvenience.

 

[rmzalbar]

1 hour ago, kheller2 said:

There seems to be an 800XL error as well (page 9):

 

The April 94 issue has what you mentioned for the 600XL:

 

Valuable! Thank you, I didn't know about these corrections. I'll review my 800XL board, this may be the answer for me.

[rmzalbar]

I cracked my 800XL back open to check for the mistakes mentioned, but I did it right the first time. Also.. testing my 800XL, the chroma level now seems fine. I think I just get spoiled if I play with my 1200XL, or my chroma-boosted 2600 too much.

[hueyjones70]

I have performed this mod 3 times and it fail to produce video every time so I always gave up and went with a UAV. At least now I know it wasn't entirely my fault.

[hueyjones70]

Is there a parts list for the 600XL PAL?

[hueyjones70]

What is needed to get composite only video on the 600XL?

[hueyjones70]

Today I tried again to perform a SuperVideo 2.1 on an 600XL; I am 0 for 5. I am getting a chroma signal. When I plug the chroma lead into the composite jack, I get some highly agitated color images. I get nothing when I plug in the Luma or the composite. I know I can install a UAV but at this point that is just accepting defeat.

Edited October 14, 2021 by hueyjones70
Correct an error

[+kheller2]

What display device are you using, and does it work with any Atari you’ve tried?

[Sugarland]

3 hours ago, hueyjones70 said:

Today I tried again to perform a SuperVideo 2.1 on an 800XL; I am 0 for 5. I am getting a chroma signal. When I plug the chroma lead into the composite jack, I get some highly agitated color images. I get nothing when I plug in the Luma or the composite. I know I can install a UAV but at this point that is just accepting defeat.

 

Post high resolution photos please? I've not done the upgrade personally so it would be up to someone else to examine them.

 

[hueyjones70]

The video components are so tightly packed that a photo would be useless. I have looked it over with a lighted magnifying glass and it is impossible to tell identify resistor strength or to see anything of value. I did clean up the solder connections and I finally got luma. Both S-Video and Composite video show up as black and white. I have obviously missed something in the color circuit.

[Panther]

The mod does work, these are the before and after photos I took of an NTSC 600XL.

 

[hueyjones70]

I finally performed the mod successfully, composite and S-Video working great. Pictures later.

[hueyjones70]

I just successfully completed another SV 2.1 on a 600XL. I found it is much easier to follow the instructions provided in the Best Electronics upgrade package. Those instructions have you install components from right to left and that makes it easier to get everything in the right place. After all the parts are installed then I replace ones that the SV 2.1 calls for. The S video is really good but the composite has a lot of color bleeding.

[Panther]

Great!  The 600XL is such a nice compact Atari (as far as original Atari's go).  It's amazing that they failed to include the monitor jack and components, given how little is required, but at least most of the spots are there for the required components, save for the chroma and luma connections to the jack.

 

[_The Doctor__]

The fixed directions should be distributed to everywhere and wherever you find the MISTAKES version.