flashjazzcat Posted March 6, 2010 Author Share Posted March 6, 2010 I think we need more info here. Does the "classic" SCART cable already have a diode in it? Does it carry an s-video or composite signal (don't forget the composite signal is gone now). A better picture of the mod might help. Quote Link to comment Share on other sites More sharing options...
w1k Posted March 8, 2010 Share Posted March 8, 2010 first testing, only BW mode, but TV pictutes is better.. Quote Link to comment Share on other sites More sharing options...
flashjazzcat Posted March 8, 2010 Author Share Posted March 8, 2010 first testing, only BW mode, but TV pictutes is better.. Yes: now we're getting somewhere. Quote Link to comment Share on other sites More sharing options...
w1k Posted March 19, 2010 Share Posted March 19, 2010 so.. svideo cable is finnished and results is FANTASTIC i add photos next week. Quote Link to comment Share on other sites More sharing options...
flashjazzcat Posted March 19, 2010 Author Share Posted March 19, 2010 so.. svideo cable is finnished and results is FANTASTIC i add photos next week. Great news. I look forward to seeing the photos. Quote Link to comment Share on other sites More sharing options...
puppetmark Posted March 21, 2010 Share Posted March 21, 2010 so.. svideo cable is finnished and results is FANTASTIC i add photos next week. Great news. I look forward to seeing the photos. Me too. Please share if you can. Quote Link to comment Share on other sites More sharing options...
w1k Posted March 21, 2010 Share Posted March 21, 2010 results for the second computer is not good.. BW screen and vertical lines still visible.. hmm Quote Link to comment Share on other sites More sharing options...
w1k Posted March 23, 2010 Share Posted March 23, 2010 tomorrow it probably already will be repaired Quote Link to comment Share on other sites More sharing options...
flashjazzcat Posted March 23, 2010 Author Share Posted March 23, 2010 tomorrow it probably already will be repaired More information would be interesting and useful. Quote Link to comment Share on other sites More sharing options...
w1k Posted March 25, 2010 Share Posted March 25, 2010 testing photos.. but vertical lines still visible http://foto.podstromami.com/albums/atari800xe/IMG_0369.jpg http://foto.podstromami.com/albums/atari800xe/IMG_0370.jpg what can be wrong? gtia? Quote Link to comment Share on other sites More sharing options...
flashjazzcat Posted March 25, 2010 Author Share Posted March 25, 2010 (edited) testing photos.. but vertical lines still visible http://foto.podstrom...xe/IMG_0369.jpg http://foto.podstrom...xe/IMG_0370.jpg what can be wrong? gtia? For my money, that looks pretty good. Is this an XL or XE? I've lost track. I managed to eradicate the vertical banding on my XL machines (see the XL UltraVideo mod), but they never completely went away on my XEs. It will also depend massively on the choice of TV/monitor. I realized this when I bought a cheap, generic second-hand LCD recently and it displayed the A8 s-video signal better than my 1080p LG... Frankly I'm disinclined to alter the A8's video output further than removing the RF mod and possibly doing all the Supervideo changes. Most of my remaining problems were solved by trying out different screens. Edited March 25, 2010 by flashjazzcat Quote Link to comment Share on other sites More sharing options...
w1k Posted March 26, 2010 Share Posted March 26, 2010 it is 800XE.. hmm, when i use LCD, then problem be resolved? or bad gtia? Quote Link to comment Share on other sites More sharing options...
flashjazzcat Posted March 26, 2010 Author Share Posted March 26, 2010 it is 800XE.. hmm, when i use LCD, then problem be resolved? or bad gtia? I don't know about bad GTIAs: supposedly the colours were way off with some of them. It's simply impossible to predict if such-and-such an LCD will work well. At the end of the day, you have to try some until you find one which looks good. Quote Link to comment Share on other sites More sharing options...
SuperSparky Posted April 15, 2010 Share Posted April 15, 2010 The silicon diode 1N4002 is a poor choice for video, especially the chroma output. It's switching voltage is 0.7 volts! Use a germanium diode instead. A 1N34A should do. Not only is its switching voltage 0.3 volts, but it's also designed to switch at high frequencies. Silicon diodes are best left to rectification. Germanium diodes typically have glass cases, and you'll notice your Atari has a lot of them. The silicon diodes are only in the power circuits. Fortunately, if you've already made this mod, and don't want to risk damaging the PC board by removing the 1N4002 diode you previously installed after removing a resistor (XE boards are delicate), then simply "piggy-back" the 1N34A diode over the 1N4002 and all will be well. Your color on edges should be more accurate, especially the screen edge. Quote Link to comment Share on other sites More sharing options...
576XE Posted February 20, 2011 Share Posted February 20, 2011 I've written up the s-video mod which has worked quite nicely for me on a couple of XE machines. It's on my projects page here, and this is the direct link to the PDF guide: UltraVideo XE 1.0 PDF Instructions I can't repeat often enough that I'm no electronics expert, and anything useful I discover usually comes about by accident. I know one or two people tried the XL version of this mod a while back and got mixed results, so I can't promise things will look as good on your TV as they do on mine. While I'm perfectly happy with the results of the XL mod, I still think the XE could be improved, so hopefully this will be a springboard for knowledgeable people to make further adjustments. Enjoy! Hi, flashjazzcat I'm admired by your investigations in 'Atarism' area. Only one comment here... There are some S-Video to VGA converters/scalers, like this one, for example, http://www.hdtvsupply.com/tv-to-pc-converter.html or this http://www.cablewholesale.com/specs/tv-to-vga/41vc-00210.htm which can make possible to connect every LCD monitor to your perfect UltraVideoXE S-Video output jack. I think it's may be useful. It's possible that the devices have not a big sizes and can be used in ATARI internally. Quote Link to comment Share on other sites More sharing options...
+Stephen Posted February 20, 2011 Share Posted February 20, 2011 Hi, flashjazzcat I'm admired by your investigations in 'Atarism' area. Only one comment here... There are some S-Video to VGA converters/scalers, like this one, for example, http://www.hdtvsupply.com/tv-to-pc-converter.html or this http://www.cablewholesale.com/specs/tv-to-vga/41vc-00210.htm which can make possible to connect every LCD monitor to your perfect UltraVideoXE S-Video output jack. I think it's may be useful. It's possible that the devices have not a big sizes and can be used in ATARI internally. I have the 2nd device, and a different model and neither one works properly with the Atari. The Atari does not use odd/even fields, so these new digital devices cannot properly decode the signal. You end up with every other frame being dropped a scanline. You also get nasty "combing" artifacts on horizontally moving objects. You get this nasty effect due to the one scanline drop issue. This is how my Dynex LCD natively decodes the s-video signal. The VGA converters do the same thing. Quote Link to comment Share on other sites More sharing options...
w1k Posted February 20, 2011 Share Posted February 20, 2011 i have UV1.0XE, but i see vertical (and new horizontal) lines.. :/ Quote Link to comment Share on other sites More sharing options...
UNIXcoffee928 Posted February 20, 2011 Share Posted February 20, 2011 ... but I am no longer patient enough or steady of hand enough to lay out a double-sided circuit board by hand. Here's a good trick for the shaky hand... Rector brand wrist guards eBay Auction -- Item Number: 400191788680. If you wear one with a fingerless glove, you can position your hand, wrist, & forearm so that it will not shake, at all, for working on fidgety stuff. Quote Link to comment Share on other sites More sharing options...
576XE Posted February 21, 2011 Share Posted February 21, 2011 Hi, flashjazzcat I'm admired by your investigations in 'Atarism' area. Only one comment here... There are some S-Video to VGA converters/scalers, like this one, for example, http://www.hdtvsupply.com/tv-to-pc-converter.html or this http://www.cablewholesale.com/specs/tv-to-vga/41vc-00210.htm which can make possible to connect every LCD monitor to your perfect UltraVideoXE S-Video output jack. I think it's may be useful. It's possible that the devices have not a big sizes and can be used in ATARI internally. I have the 2nd device, and a different model and neither one works properly with the Atari. The Atari does not use odd/even fields, so these new digital devices cannot properly decode the signal. You end up with every other frame being dropped a scanline. You also get nasty "combing" artifacts on horizontally moving objects. You get this nasty effect due to the one scanline drop issue. This is how my Dynex LCD natively decodes the s-video signal. The VGA converters do the same thing. Hi, Stephen. Thank you for your reply. I had intention to buy some kind of these devices, but after your post I'm in trouble now. How do you think is it incorrect NTSC/PAL conversion problem or exclusively progressive/interlaced mode incompartibility? I know that S-Video standard does not contain any information about interlacing or syncronisation. The artifacts showed by you in your blog is very strange especially regular columns squeezing. And what about clear picture showed by flashjazzcat? Best regards from Moscow. Quote Link to comment Share on other sites More sharing options...
+Stephen Posted February 21, 2011 Share Posted February 21, 2011 Hi, Stephen. Thank you for your reply. I had intention to buy some kind of these devices, but after your post I'm in trouble now. How do you think is it incorrect NTSC/PAL conversion problem or exclusively progressive/interlaced mode incompartibility? I know that S-Video standard does not contain any information about interlacing or syncronisation. The artifacts showed by you in your blog is very strange especially regular columns squeezing. And what about clear picture showed by flashjazzcat? Best regards from Moscow. I don't think it has to do with NTSC/PAL issues, as I am fortunate enough to own both. All of my Ataris display nicely on OLD CRT TVs, and the Commodore 1084S monitor. Any new TV I have tried them on, whether it is a CRT or LCD, look the same with the bad vertical banding. Many people believe this banding to be caused by DMA refresh "bleeding" into the video signal. I am not a hardware guy, so I can't comment. Another thing to remember, is the video on these old machines is analog, and WAY out of spec. With the new modern devices all being digital, most will have a hard time properly decoding a signal which is this far out of spec. flashjazzcat has indeed posted some very nice results with LCD screens. Hopefully someone here with more experience that I will post some more suggestions. I have been very unlucky with mine - 5 Ataris tested across 6 different display devices, all with the same crappy results. Quote Link to comment Share on other sites More sharing options...
w1k Posted March 3, 2011 Share Posted March 3, 2011 my screen is still not good i trying it on different CRT tvs Quote Link to comment Share on other sites More sharing options...
mimo Posted March 3, 2011 Share Posted March 3, 2011 I see the problem , some idiot had drawn an arrow on your tv screen Quote Link to comment Share on other sites More sharing options...
flashjazzcat Posted March 3, 2011 Author Share Posted March 3, 2011 I realize - in light of KJMann's excellent experimentation with the Atari video circuit - that I was using a sledgehammer to crack a nut with the Ultravideo mod. Sal's mod is unbelievably simple and highly effective. Quote Link to comment Share on other sites More sharing options...
spookt Posted March 4, 2011 Share Posted March 4, 2011 (edited) I see the problem , some idiot had drawn an arrow on your tv screen PMSL :D Edited March 4, 2011 by spookt Quote Link to comment Share on other sites More sharing options...
w1k Posted March 4, 2011 Share Posted March 4, 2011 whatever Quote Link to comment Share on other sites More sharing options...
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