Schmutzpuppe Posted January 13, 2004 Share Posted January 13, 2004 Those are timing signals in the picture. Where they there before the mod? I'm noticing that the power routing isn't as clean in the Rev D board. I'm gonna do some experiments and get back to you. -Bry Those distortions are the norm on PAL XE Systems. Or should I say every XE I saw had those distortions on the screen. Can't confirm that, my first modded XL has much more distortions (picture above) than the second one. Quote Link to comment Share on other sites More sharing options...
emkay Posted January 13, 2004 Share Posted January 13, 2004 Those are timing signals in the picture. Where they there before the mod? I'm noticing that the power routing isn't as clean in the Rev D board. I'm gonna do some experiments and get back to you. -Bry Those distortions are the norm on PAL XE Systems. Or should I say every XE I saw had those distortions on the screen. Can't confirm that, my first modded XL has much more distortions (picture above) than the second one. I tried to say that stock XL computers never had such distortions, but every stock (130) XE I have seen, has such distortions. I never saw a PAL XE without this problem. That's one cause why I still prefer the XL series. Quote Link to comment Share on other sites More sharing options...
Bryan Posted January 13, 2004 Author Share Posted January 13, 2004 I tried to say that stock XL computers never had such distortions, but every stock (130) XE I have seen, has such distortions. I never saw a PAL XE without this problem. That's one cause why I still prefer the XL series. It seems the XL solution to the noise was to blur it out. I'm hoping Schmutzpuppe has good results, and the wire bypasses the noise sources altogehter, in which case it might be time to look at improving PAL XE's. -Bry Quote Link to comment Share on other sites More sharing options...
Schmutzpuppe Posted January 13, 2004 Share Posted January 13, 2004 I tried to say that stock XL computers never had such distortions, but every stock (130) XE I have seen, has such distortions. I never saw a PAL XE without this problem. That's one cause why I still prefer the XL series. It seems the XL solution to the noise was to blur it out. I'm hoping Schmutzpuppe has good results, and the wire bypasses the noise sources altogehter, in which case it might be time to look at improving PAL XE's. -Bry Good work (again) Bry, less distortion not completely vanished but much weaker. The difference on the upgraded XL is much stronger visible. On the second modded XL the difference isn't that big but the picture of this machine hasn't much distortion before. Thanks Matthias Quote Link to comment Share on other sites More sharing options...
Schmutzpuppe Posted January 13, 2004 Share Posted January 13, 2004 Those are timing signals in the picture. Where they there before the mod? I'm noticing that the power routing isn't as clean in the Rev D board. I'm gonna do some experiments and get back to you. -Bry Those distortions are the norm on PAL XE Systems. Or should I say every XE I saw had those distortions on the screen. Can't confirm that, my first modded XL has much more distortions (picture above) than the second one. I tried to say that stock XL computers never had such distortions, but every stock (130) XE I have seen, has such distortions. I never saw a PAL XE without this problem. That's one cause why I still prefer the XL series. Ok, I see. My fault Matthias Quote Link to comment Share on other sites More sharing options...
+bob1200xl Posted August 10, 2007 Share Posted August 10, 2007 Those are timing signals in the picture. Where they there before the mod? I'm noticing that the power routing isn't as clean in the Rev D board. I'm gonna do some experiments and get back to you. -Bry Those distortions are the norm on PAL XE Systems. Or should I say every XE I saw had those distortions on the screen. That noise usually comes from "ground bounce". The impedance of the ground return puts noise in the video signals. If you increase the video AC current, (by lowering the output impedance of the driver, for example) you make it worse. All the video is presented as a digital signal by GTIA and ANTIC - converting it to analog is the killer. Someday, maybe someone could run the digital signals through an opto-isolator and construct the little bit of circuitry needed to generate nice video - on a little PCB with a ground plane and DIN connector. The 1450XL has a ground plane motherboard, you know... Bob Quote Link to comment Share on other sites More sharing options...
tjlazer Posted September 4, 2007 Share Posted September 4, 2007 (edited) I finally got around to performing this in my two 800XL's. Some observations. I am using a Commodore 1702 monitor with seperate chroma/luma. This yields the best picture IMHO. Both machines are Rev C. First one has every single chip in sockets! This one had the blurry video. C56 was in tact. I did this mod except for the last step of adding the 1K Chroma Feedback Resistor mod (Solder a 1K resistor from the bottom of R58 to the right side of C55.) This did nothing. The video is dramatically better! I also removed L5 and rerouted the power line. Could not tell a difference but I did it anyway. The second one has most chips in sockets except for OS/Basic. C56 was already removed, along with R57. After doing the Chroma mod the video got a tad better but was already pretty good. It seems to be very close to the first one so I just left it alone at this point. Keyboard is bad in this one so it's more of a parts computer. When I just did this mod, I tested the video at each stage on my Commodore 1702 monitor. In fact the most noticeable step was removing C56... I am fairly convinced that this step alone is good enough as I could not tell the difference when I did the rest... Edited September 4, 2007 by tjlazer Quote Link to comment Share on other sites More sharing options...
Sincity Posted September 11, 2007 Share Posted September 11, 2007 L5 Question: Per Bryan's revised instruction, I am a little confused. Do I: 1) Remove L5 entirely 2) Add a jumper across L5 or just: 1) Remove L5 entirely. Thanks. Quote Link to comment Share on other sites More sharing options...
tjlazer Posted September 12, 2007 Share Posted September 12, 2007 (edited) L5 Question: Per Bryan's revised instruction, I am a little confused. Do I: 1) Remove L5 entirely 2) Add a jumper across L5 or just: 1) Remove L5 entirely. Thanks. L5Remove L5 (or at least lift one leg of it out of the board). This will break the old 5V path. New Power Lead Solder a wire from the front lead of C3 (electrolytic to the right of the power jack) to the front lead of C51 (or the front hole of L5 is directly connected to C51 and can be used). If you run this wire along the RF modulator, it should clear the shield. 20 or 24 gauge wire should work well. Remove L5 and run a wire from the bottom part of it to C3 (near the power connector) Edited September 12, 2007 by tjlazer Quote Link to comment Share on other sites More sharing options...
Sincity Posted October 11, 2007 Share Posted October 11, 2007 I hope removing L5 and re-routing power will remove the faint vertical bars. Not sure of MB revision, though. Quote Link to comment Share on other sites More sharing options...
Sincity Posted October 12, 2007 Share Posted October 12, 2007 I hope removing L5 and re-routing power will remove the faint vertical bars. Not sure of MB revision, though. Did this MOD and it removed all of my vertical bars. Now I have to add the resisters to complete the MOD. Quote Link to comment Share on other sites More sharing options...
ClausB Posted March 28, 2008 Share Posted March 28, 2008 My 800XL is Rev. C with all sockets and the Quarter-Meg mod. So far, I only clipped the cap and added the chroma output and made an S-video cable. Star Raiders looked poor with shields on before, but now it looks great on the big screen! Thanks to all for the informative posts. Quote Link to comment Share on other sites More sharing options...
Reaperman Posted March 28, 2008 Share Posted March 28, 2008 (edited) My 800XL is Rev. C with all sockets and the Quarter-Meg mod. So far, I only clipped the cap and added the chroma output and made an S-video cable. Star Raiders looked poor with shields on before, but now it looks great on the big screen! Thanks to all for the informative posts. sounds like we have exactly the same system down to the 256k. I've been saddened by my video lately and I'll have to do at least that part of the mod. Does it kill artifacting color? I never remember my childhood infront of an 800xl looking so bad, and I'm sure it didn't. Edited March 28, 2008 by Reaperman Quote Link to comment Share on other sites More sharing options...
ClausB Posted March 28, 2008 Share Posted March 28, 2008 Does it kill artifacting color? I never remember my childhood infront of an 800xl looking so bad, and I'm sure it didn't. Using the S-video connection does kill artifact color, a good thing IMO. If you use the composite video output, though, you still get artifact color. I doubt your XL got worse - it's just that TVs have got so much better in 25 years. Quote Link to comment Share on other sites More sharing options...
athleos Posted March 28, 2008 Share Posted March 28, 2008 hey guys... i haven't had the chance to open my computer up yet but i was wondering if the circuits were close enough for this mod to work on my 600XL? is this mod better than the one from Best Electronics? thanks. Quote Link to comment Share on other sites More sharing options...
puppetmark Posted March 29, 2008 Share Posted March 29, 2008 hey guys... i haven't had the chance to open my computer up yet but i was wondering if the circuits were close enough for this mod to work on my 600XL? is this mod better than the one from Best Electronics? thanks. Is Your 600XL NTSC or PAL? Quote Link to comment Share on other sites More sharing options...
athleos Posted March 29, 2008 Share Posted March 29, 2008 hey guys... i haven't had the chance to open my computer up yet but i was wondering if the circuits were close enough for this mod to work on my 600XL? is this mod better than the one from Best Electronics? thanks. Is Your 600XL NTSC or PAL? NTSC Quote Link to comment Share on other sites More sharing options...
puppetmark Posted March 29, 2008 Share Posted March 29, 2008 hey guys... i haven't had the chance to open my computer up yet but i was wondering if the circuits were close enough for this mod to work on my 600XL? is this mod better than the one from Best Electronics? thanks. Is Your 600XL NTSC or PAL? NTSC The 600XL video circuits in a NTSC machine are a stripped down version of the 800XL circuits. And you can do a couple of the same changes that are in this thread and it will make a small improvement but you still don't have a monitor jack. So then you have 2 choices: 1. this is the same as the Best electronics MOD: http://atrey.karlin.mff.cuni.cz/~pavel/atari/600xlmon.html 2. This one is better BUT it is not easy and if you don't have electronic experience I would not recomend it: http://www.wolfpup.net/atarimods/supervid4.html Quote Link to comment Share on other sites More sharing options...
Reaperman Posted March 29, 2008 Share Posted March 29, 2008 I doubt your XL got worse - it's just that TVs have got so much better in 25 years. oh no, my old 800xl melted into a puddle in a house fire when I was 11--I'm comparing my new system to what I remember of the old one, and it just doesn't stack up. Quote Link to comment Share on other sites More sharing options...
athleos Posted March 30, 2008 Share Posted March 30, 2008 hey guys... i haven't had the chance to open my computer up yet but i was wondering if the circuits were close enough for this mod to work on my 600XL? is this mod better than the one from Best Electronics? thanks. Is Your 600XL NTSC or PAL? NTSC The 600XL video circuits in a NTSC machine are a stripped down version of the 800XL circuits. And you can do a couple of the same changes that are in this thread and it will make a small improvement but you still don't have a monitor jack. So then you have 2 choices: 1. this is the same as the Best electronics MOD: http://atrey.karlin.mff.cuni.cz/~pavel/atari/600xlmon.html 2. This one is better BUT it is not easy and if you don't have electronic experience I would not recomend it: http://www.wolfpup.net/atarimods/supervid4.html thanks for the info! i have the Best Electronics MOD but i was looking for more and seeing as i have electronic experience, i may be able to pull off Supervid2.1XL. thanks again!! Quote Link to comment Share on other sites More sharing options...
puppetmark Posted March 30, 2008 Share Posted March 30, 2008 thanks for the info! i have the Best Electronics MOD but i was looking for more and seeing as i have electronic experience, i may be able to pull off Supervid2.1XL. thanks again!! Cool. I have done the 600XL Supervid2.1 a couple of times. The trickiest part is reading the part locations on the 600XL motherboard. The markings are not always clear. If you need help, let me know. You will be very impressed with the video after the upgrade. If you use your 600xl everyday then the work involved is probably worth it. The output is even better with an s-video input tv or monitor. Good luck! Quote Link to comment Share on other sites More sharing options...
athleos Posted March 31, 2008 Share Posted March 31, 2008 thanks for the info! i have the Best Electronics MOD but i was looking for more and seeing as i have electronic experience, i may be able to pull off Supervid2.1XL. thanks again!! Cool. I have done the 600XL Supervid2.1 a couple of times. The trickiest part is reading the part locations on the 600XL motherboard. The markings are not always clear. If you need help, let me know. You will be very impressed with the video after the upgrade. If you use your 600xl everyday then the work involved is probably worth it. The output is even better with an s-video input tv or monitor. Good luck! hey thanks man! i'll let you know how it goes. i may have questions so i'm glad i know someone who has already done the mod. Quote Link to comment Share on other sites More sharing options...
Kjmann Posted January 16, 2009 Share Posted January 16, 2009 to solve the problem with the clock lines, add a silicon diode in to the chroma line. you can add a resistor for saturation preference. adjust to your preference between 2.2 ohms and 10 ohms. Quote Link to comment Share on other sites More sharing options...
+Stephen Posted January 16, 2009 Share Posted January 16, 2009 to solve the problem with the clock lines, add a silicon diode in to the chroma line. you can add a resistor for saturation preference. adjust to your preference between 2.2 ohms and 10 ohms. kjmann - would the resistor and diode go inline between the chroma line and monitor pin, or does it get jumpered across the chroma pin and ground? Stephen Anderson Quote Link to comment Share on other sites More sharing options...
Kjmann Posted January 17, 2009 Share Posted January 17, 2009 (edited) to solve the problem with the clock lines, add a silicon diode in to the chroma line. you can add a resistor for saturation preference. adjust to your preference between 2.2 ohms and 10 ohms. kjmann - would the resistor and diode go inline between the chroma line and monitor pin, or does it get jumpered across the chroma pin and ground? Stephen Anderson It goes inline. I used a diode and a 2.2ohm 1/4 watt resistor. It solved the problem with my unit. One thing is that the more powerful the luma is, the more clock lines you get but toning down the chroma seems to solve the problem to a point. if you have your luma boosted very high you may still get some clock line problems. Edited January 17, 2009 by kjmann Quote Link to comment Share on other sites More sharing options...
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