marauder666 Posted January 22, 2019 Share Posted January 22, 2019 My PAL 130XE has an odd problem, with what looks like colour bleed, this happens over RF, composite and S-video. I've changed the 4050, and the emitter follower transistors connected to the chroma and luma outputs, no change. All electrolytics have been changed. Other the the bleed on certain colours, the picture is excellent. Most games do not show it. Tested with a 65XE, and this problem doesnt happen. Anyone else seen anything like this? Quote Link to comment Share on other sites More sharing options...
+Nezgar Posted January 22, 2019 Share Posted January 22, 2019 Have you confirmed it also happens on a different TV/Monitor? Quote Link to comment Share on other sites More sharing options...
marauder666 Posted January 22, 2019 Author Share Posted January 22, 2019 Have you confirmed it also happens on a different TV/Monitor? Yeah. Quote Link to comment Share on other sites More sharing options...
_The Doctor__ Posted January 24, 2019 Share Posted January 24, 2019 scart wiring issue? Quote Link to comment Share on other sites More sharing options...
+tf_hh Posted January 24, 2019 Share Posted January 24, 2019 My PAL 130XE has an odd problem, with what looks like colour bleed, this happens over RF, composite and S-video. Anyone else seen anything like this? Yes, sometimes. IMHO two three reasons cause this issue: - Defect PAL sync color clock circuit - GTIA itself - Combining Luminance & Chrominance the dirty way like Atari did it Specially at the XE series I found relative often a defect 74LS74 (or sometimes also used: 74HCTLS74). This one is located near the BASIC ROM and and syncs the PAL color carrier frequency with the system clock. Most times it just broke, so no color appears and you get a black & white picture only. But in some cases color bleeding or wrong colors also occurs. I would strongly suggest to change it. Second trouble maker is the GTIA itself. In some rare cases there´s a timing difference betwen the color-output and luminance plus sync. This effect changes after 20 or 30 minutes of operation slightly. I saw this only at PAL GTIAs and only at the AMI ones used in the XE series - but these GTIAs are not the one with the well-known "chinese PAL GTIA issue". At last the not very well done mixing of Chroma and Luma to get composite video may be the problem. As you´re able to use S-Video, I suggest to remove the RF modulator for a test - disables composite video, but S-Video works fine. 1 Quote Link to comment Share on other sites More sharing options...
marauder666 Posted January 24, 2019 Author Share Posted January 24, 2019 Thanks. I’ll pull the modulator today, and check. If its still the same I’ll order a 74ls74. Quote Link to comment Share on other sites More sharing options...
marauder666 Posted January 24, 2019 Author Share Posted January 24, 2019 Need to order a 74LS74. The same without the modulator. Hopefully it won't need a GTIA. Quote Link to comment Share on other sites More sharing options...
marauder666 Posted January 28, 2019 Author Share Posted January 28, 2019 Need to order a GTIA. Just the same with a new 74LS74 Quote Link to comment Share on other sites More sharing options...
_The Doctor__ Posted January 28, 2019 Share Posted January 28, 2019 (edited) the more I see your image the more I think this has been posted about before on the forums here, someone who has great search-fu might be able to dig it up for you. it may even be mixed in with some talk about television/monitor tearing... which was a an issue for bad or failing displays back in the day, while you have ruled the monitor out as it occurs on other displays... it may well have been part of that discussion as well. Good luck, maybe the GTIA will sort it.... if not, time to look at the crystal/ color clock circuits... Edited January 28, 2019 by _The Doctor__ Quote Link to comment Share on other sites More sharing options...
marauder666 Posted January 28, 2019 Author Share Posted January 28, 2019 (edited) Now I've left it running for a couple of hours, the bleed is less, but still there. Guess its the GTIA problem mentioned earlier. This board does only have one socketed IC, the GTIA. At least I don't have to unsolder it. Edited January 28, 2019 by marauder666 Quote Link to comment Share on other sites More sharing options...
_The Doctor__ Posted January 28, 2019 Share Posted January 28, 2019 odd that it's the only one in a socket, perhaps it was an issue someone tried to fix it. Quote Link to comment Share on other sites More sharing options...
flashjazzcat Posted January 28, 2019 Share Posted January 28, 2019 Some of them came out of the factory with just the GTIA in a socket, which is interesting and suggests issues were discovered during testing. 3 Quote Link to comment Share on other sites More sharing options...
+tf_hh Posted January 29, 2019 Share Posted January 29, 2019 Some of them came out of the factory with just the GTIA in a socket, which is interesting and suggests issues were discovered during testing. Yes, I also have had a dozen or so PAL XE systems with only GTIA in a socket. This socket was installed during initial production stage (soldering bath) and NOT manually afterwards. IMHO this may be proof for the fact, that Atari engineering did know they have problems with some GTIA during the XE production times. And maybe - conspiracy mode on - Tramiel also knows that, but decide to ignore it. 3 Quote Link to comment Share on other sites More sharing options...
marauder666 Posted January 29, 2019 Author Share Posted January 29, 2019 Jack would ignore it. 99% of PAL XEs in the 80s would have been plugged into a crappy little TVs using RF. The bleed wouldnt have been noticeable. Quote Link to comment Share on other sites More sharing options...
marauder666 Posted February 1, 2019 Author Share Posted February 1, 2019 New GTIA appears to have fixed it. Thanks for all your help. 3 Quote Link to comment Share on other sites More sharing options...
_The Doctor__ Posted February 1, 2019 Share Posted February 1, 2019 please post macro focus image of bad chip and text version of the info that is printed on it, gathering data like this will help nail down the failures and make things better and easier for servicing the machines of the entire community... 1 Quote Link to comment Share on other sites More sharing options...
marauder666 Posted February 1, 2019 Author Share Posted February 1, 2019 (edited) November 1984, new one is August 1987 8734 AMI 8448MDH C014889-01 © C04085 PHILIPPINES Edited February 1, 2019 by marauder666 2 Quote Link to comment Share on other sites More sharing options...
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