wolhess Posted April 18, 2020 Share Posted April 18, 2020 A few weeks ago I found a bug in one of my TI consoles. The screen display no longer functioned correctly from normal operation. I then opened the console according to the instructions from here and, as described in the article from here, unsoldered the probably defective DRAM chip. I ordered some TMS4116 chips from China some time ago. I then inserted one of them into the IC socket. With the new chip, however, the screen remained black. I then tried a few china chips, but always with a black screen. When I simply left out the chip, I got the incomplete screen again! This is the bad Chip from China! Today I got a new delivery of NEC D416C -3 IC's, exactly these were also installed on the board. After inserting one of these ICs, the TI has a complete picture again. This is the good chip! Everything seems to work as usual! 20 1 Quote Link to comment Share on other sites More sharing options...
Omega-TI Posted April 18, 2020 Share Posted April 18, 2020 Congrats! Nothing better than success! 3 Quote Link to comment Share on other sites More sharing options...
atrax27407 Posted April 18, 2020 Share Posted April 18, 2020 Maybe the Chinese chip had a virus ? 5 Quote Link to comment Share on other sites More sharing options...
Papalapa Posted April 19, 2020 Share Posted April 19, 2020 Nice and quick job, congratulations. It's an NTSC or PAL TI-99/4A?. How do you connect the TI-99/4A to the LCD monitor? 1 Quote Link to comment Share on other sites More sharing options...
wolhess Posted April 19, 2020 Author Share Posted April 19, 2020 7 hours ago, Papalapa said: Nice and quick job, congratulations. It's an NTSC or PAL TI-99/4A?. How do you connect the TI-99/4A to the LCD monitor? Thank You, the console is a PAL one and connected with a PHA 2036 Modulator to the RF Input of the LCD TV. Today I used a direct cable from the DIN 6pol. port of the TI to another LCD TV with YPbBr input. This was a second small project. I will post some pictures tomorrow. This way it gives me a much better picture. 1 Quote Link to comment Share on other sites More sharing options...
Papalapa Posted April 19, 2020 Share Posted April 19, 2020 27 minutes ago, wolhess said: Thank You, the console is a PAL one and connected with a PHA 2036 Modulator to the RF Input of the LCD TV. Today I used a direct cable from the DIN 6pol. port of the TI to another LCD TV with YPbBr input. This was a second small project. I will post some pictures tomorrow. This way it gives me a much better picture. I don't achieved to have a good image with my PAL TI-99/4A. I have no RF modulator but even having one I guess that the image quality will be bad. I tried several TVs/monitors LCD and TRC but the colors on the screen are always wrong and most of times out of sync. Even I installed the Citrus3000 chip to convert the video ouptut to RGB unsuccesfully and actually I'm using the luminance output of the 6-pin DIN but in this case I only get a B/W signal on the monitor of course. It will be great to see your pcitures tomorrow... Quote Link to comment Share on other sites More sharing options...
wolhess Posted April 19, 2020 Author Share Posted April 19, 2020 On my main system I use a Sony Bravia KDL-19BX200 LCD TV with a PHA 2036 RF modulator. This one has a very good picture, but the YPbBr cable direct to the LCD TV is better. Quote Link to comment Share on other sites More sharing options...
wolhess Posted April 20, 2020 Author Share Posted April 20, 2020 This is the screen from my Sony LCD TV with a PHA 2036 RF modulator: And this is the screen with a direct YPbPr cable The colors are good, but the picture is not very sharp The colors are lightly better on the LCD TV but the picture is very sharp and clean The more blue is only on the photo. In reality I see yellow as yellow and brown as brown. And I can center the picture on the LCD screen This is a picture with a PHA 2036 on the odys LCD TV 15-BASE The Sony is much better! 1 Quote Link to comment Share on other sites More sharing options...
Sid1968 Posted April 20, 2020 Share Posted April 20, 2020 Gute Arbeit, Wolfgang! Vielleicht hast Du ja auch noch Lust auf einen Elko-Tausch. 1 Quote Link to comment Share on other sites More sharing options...
+acadiel Posted April 20, 2020 Share Posted April 20, 2020 These DRAMs seem like the most problematic thing. Is there a way to yank all eight of them and replace them with one? Quote Link to comment Share on other sites More sharing options...
Sid1968 Posted April 20, 2020 Share Posted April 20, 2020 (edited) 34 minutes ago, acadiel said: These DRAMs seem like the most problematic thing. Is there a way to yank all eight of them and replace them with one? No. I already exchanged some 4116 with U256D RAM from the former German Democratic Republic. There are like 4116 and work good. Advice to find defective ram chips: If you want to find a defective RAM-Chip set a good 4116 in piggyback above each chip. If the error is gone you are at the defective one. But you should test if there are more ram chips defective. Watch out that you put the test-ramchip in the right direction on the others. Edited April 20, 2020 by Sid1968 4 Quote Link to comment Share on other sites More sharing options...
Papalapa Posted April 20, 2020 Share Posted April 20, 2020 7 hours ago, wolhess said: This is the screen from my Sony LCD TV with a PHA 2036 RF modulator: And this is the screen with a direct YPbPr cable The colors are good, but the picture is not very sharp The colors are lightly better on the LCD TV but the picture is very sharp and clean The more blue is only on the photo. In reality I see yellow as yellow and brown as brown. And I can center the picture on the LCD screen This is a picture with a PHA 2036 on the odys LCD TV 15-BASE The Sony is much better! It is very interesting and surprising because it seems that with the Sony TV and the PHA 2036 RF modulator although the picture is not sharp at least you have the right colors on the screen. I also have a 14" 4:3 LCD Sony TV for my retrocomputers collection but I don't have the RF modulator. Even you can get the video composite signal inside the modulador in order to get better picture in the screen. Until now I tried YPbPr to VGA, HDMI and RGB converters unsuccesfully with both, TRC and LCD displays and even connecting the YPbPr TI-99/4A output directly to theSony TV but colors were always incorrect. May be the solution is to find an PHA 2036 RF modulator.... 1 Quote Link to comment Share on other sites More sharing options...
wolhess Posted April 20, 2020 Author Share Posted April 20, 2020 For me the best picture currently is with a PHA 2036 and the Sony LCD TV. But I will try some other configurations in the Next days. I have a PHA 2037 (RGB Modulator) too and I bought a line doubler OSSC from https://videogameperfection.com/products/open-source-scan-converter/ So I have some possibilities. The best will be a FA18A mk2, when it is available. Quote Link to comment Share on other sites More sharing options...
J-Data Posted April 20, 2020 Share Posted April 20, 2020 On 4/18/2020 at 10:31 AM, wolhess said: I then tried a few china chips, but always with a black screen. I think I got some of the same bad TMS4116 ICs from from China. Where they from Huayi Components by any change? The -5V inputs were a dead short on half of mine, and none worked. Reordered from a US distributor at 10x the cost and all worked fine. Nice job on the repair. 1 Quote Link to comment Share on other sites More sharing options...
+arcadeshopper Posted April 20, 2020 Share Posted April 20, 2020 please don't buy 4116 .. 4164 runs cooler, lasts longer, uses less power and..are cheap and can replace the 4116 with small modifications 3 Quote Link to comment Share on other sites More sharing options...
twoodland Posted April 21, 2020 Share Posted April 21, 2020 Great job wolhess! Wonderful troubleshooting! Inspirierend! 1 Quote Link to comment Share on other sites More sharing options...
Sid1968 Posted April 21, 2020 Share Posted April 21, 2020 15 hours ago, arcadeshopper said: please don't buy 4116 .. 4164 runs cooler, lasts longer, uses less power and..are cheap and can replace the 4116 with small modifications What modifications? Quote Link to comment Share on other sites More sharing options...
Omega-TI Posted April 21, 2020 Share Posted April 21, 2020 When replacing "Elkos" in this day and age, where would one find the most high-quality, high-end, longest lasting caps? If I'm gonna do this too, I don't want to go through all the time and effort to install cheap Chinese crap that will fail in a couple of years. I want my TI to outlive me. Quote Link to comment Share on other sites More sharing options...
Sid1968 Posted April 21, 2020 Share Posted April 21, 2020 (edited) 5 minutes ago, INVISIBLE said: When replacing "Elkos" in this day and age, where would one find the most high-quality, high-end, longest lasting caps? If I'm gonna do this too, I don't want to go through all the time and effort to install cheap Chinese crap that will fail in a couple of years. I want my TI to outlive me. Look in my thread. I gave productlinks. Edited April 21, 2020 by Sid1968 1 Quote Link to comment Share on other sites More sharing options...
+Lee Stewart Posted April 21, 2020 Share Posted April 21, 2020 15 minutes ago, Sid1968 said: What modifications? See this thread: Replacing 4116 ram with 4164 for reliability ...lee 4 Quote Link to comment Share on other sites More sharing options...
+dhe Posted April 21, 2020 Share Posted April 21, 2020 Given my recent bad experience with ChinaRam, I believe a basic TL866 programmer is worth the money, just for it's ability to check ram! It would seem the forging bad chips has become a really industry in China. Quote Link to comment Share on other sites More sharing options...
+Schmitzi Posted April 21, 2020 Share Posted April 21, 2020 21 hours ago, wolhess said: For me the best picture currently is with a PHA 2036 and the Sony LCD TV. But I will try some other configurations in the Next days. I have a PHA 2037 (RGB Modulator) too and I bought a line doubler OSSC from https://videogameperfection.com/products/open-source-scan-converter/ So I have some possibilities. The best will be a FA18A mk2, when it is available. The (french) PHA2037 with Scart is good, but not as good as your screen showed here, with the Sony.... Or my 2 PHA2037er have "problems", but I don´t believe so 1 Quote Link to comment Share on other sites More sharing options...
Sid1968 Posted April 21, 2020 Share Posted April 21, 2020 (edited) 1 hour ago, dhe said: Given my recent bad experience with ChinaRam, I believe a basic TL866 programmer is worth the money, just for it's ability to check ram! It would seem the forging bad chips has become a really industry in China. Remembers me at the 3,5" PC NoName-Diskettes in the 1990s... where a lot of had blockerrors. I had packages where only 2 of 10 where good. Edited April 21, 2020 by Sid1968 Quote Link to comment Share on other sites More sharing options...
Sid1968 Posted April 21, 2020 Share Posted April 21, 2020 (edited) 47 minutes ago, Schmitzi said: The (french) PHA2037 with Scart is good, but not as good as your screen showed here, with the Sony.... Or my 2 PHA2037er have "problems", but I don´t believe so I cant believe that i have the opportunity to link my Elko-Change thread a third time in this thread.... Thx. Since i changed the Elkos of my PHA2037 too, i show there the picture quality on my LCD-Monitor after the Elko-Change. Edited April 21, 2020 by Sid1968 1 Quote Link to comment Share on other sites More sharing options...
wolhess Posted April 21, 2020 Author Share Posted April 21, 2020 2 hours ago, Schmitzi said: The (french) PHA2037 with Scart is good, but not as good as your screen showed here, with the Sony.... Or my 2 PHA2037er have "problems", but I don´t believe so Yes, I have a 2037 too and my picture is also not so good as the Sony with the PHA 2036. Maybe I will test to change the Elkos! 2 Quote Link to comment Share on other sites More sharing options...
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