Jump to content


  • Content Count

  • Joined

  • Last visited

Everything posted by pcrock

  1. I think the arrows are pointing clockwise. When the lowest resistance is reached, full clockwise is also achieved. But this is not a problem. Testing is very easy. If not, just invert the wire to the other contact of the potentiometer. Remembering that the center (cursor) does not change.
  2. Thanks a lot friend. I did the 4050 mod and removed only the sound oscilator (transistor, inductor and the resistor that is the way to mix the signal to video). I build two ones. Used 74HC4050. The results was GREAT!!!! My consoles are NTSC versions. Tried a lot lot lot of simple av mod versions, (with 0, 1, 2 and 3 transistors) but all of then was terrible. The only one that gave me a CLEAN and PERFECT SCREEN with NO INTERFERENCES and NO NOISY PICTURES is even the 74HC4050 MOD .
  3. Hi friends, please.. Where do I find cartridges connector that fits perfect on a Vader´s atari 2600 console?? Thanks
  4. The UM6526P1 is indeed the PAL version of the TIA. ( I think is the same as CO11903) and both may have NO THE SAME pinouts than 6526N!!!!!! UM6526N, KSC131 and CO10444D, are the NTSC version!!! Please take a look below for more...
  5. I did it. Tried on several TV devices, CRT and LED ones but the issues always was there. On CRT TVs the issues was less than in Led TVs but still is there. On led TV the issues was too much!!! Using the 4050 mod at the same TVs devices as did before, all work perfect. All the pictures I posted here was taken using the same TV device. The issues pics and the solved pics are at the same screen device.
  6. Here in Brazil it is expensive and hard to find. What is the country you live??? Maybe in your country could to be simple and cheap.. thru Internet
  7. It seems to be a problem at TIA CHIP. Is the TIA soldered to the board or does it use a socket? If it is soldered, try resolding it and if it is in a socket, try a new socket and cleaning all the CHIP terminals before reinstalling it. The CHIP may also be defective.
  8. It seems to be a problem at TIA CHIP. Is the TIA soldered to the board or does it use a socket? If it is soldered, try resolding it and if it is in a socket, try a new socket and cleaning all the CHIP terminals before reinstalling it. The CHIP may also be defective. You could also have any SOUND oscillator´s signal being mixed with the video signal. Did you remove the transistor and inductor from the audio mixer oscillator circuit? May I see the schematics for the console you own???
  9. Hi @alex_79 Sorry for rebirth an old post but please let me know.. You tell that used the https://atariage.com/2600/faq/index.html?SystemID=2600#composite (4050 schematic) for build your project. My question is. On the real console there are already several components to make the Lum 0, Lum1, Lum2, Color and Sync lines up to the RF MODULATOR´s input. Should I leave those components as they are or should I remove them from the Atari board? If I leave them as they are, won't they interfere with the signal from pins 2, 5, 7 and 8 of the TIA CHIP that I will use for the new 4050 MOD circuit I am building? Thank you friend.
  10. Thanks for replying friend. I live in Brazil. UAV really appears to be the best choice (and very cheap to most of worldwide money) but unfortunately, due brazilian money currency, the total cost for it plus (cheapest) shipping is very very very expensive . 😥😥
  11. Nobody???? An update. I tried a new TIA chip and a new x200 NTSC xtal but the issues remains the same. When I set the color switch to B/W the colors goes off but is still possible to see the interferences. The console appears to be ok. About the mod circuit, all connections is as short as is possible, good ground. I can't understand the reason to all issues.
  12. Only a curious thing. Found this schematics in the internet. What do you all think???
  13. @the_crayon_king thanks once more. My great interest on this mod is that it takes the video information all ready to use at RF modulator. The CD4050 mod works very well but to build it and install it takes a lot more of time and work. And we must to put and tie the pcb (bigger than the other mod) in some place instead only to soldering in original modulator holes.
  14. @simon.plata @the_crayon_king Thanks for replying!!! About the audio, sure. The first I made before to start the mod I removed transistor, inductor, resistors and caps. Impossible audio to mix with video because audio oscillator no longer exist! Could it be a ntsc system color issue?? Don't know what is the matter. ,,,😥
  15. I just tested in LED TV. The results were very very very very BAD!!!! ahahahahah I tested both consoles with the same AV cable, same power supply, same LED TV and same cartridges! The one that uses the CD4050 AV mod works very impressive well!!! But the one with the AV mod we are discussing here shows a very poor quality screen with a lot of interferences and ghost. Now I can see that even in CRT tv, the interferences exist (not so bad as in LED screen but it is still there). Below I post the last pics about the AV circuit from the friend Simon.Plata Below I post the issues at LED TV Below I post some Pics from the console using CD4050 AV mod. Very clean, great colors and sharp graphics. If you see any issue in the pics below is from my cellphone camera. Actual graphics is very impressive good! The black Background is very clean with no interferences or noisy issues. If someone have any idea, I really would like to use the circuit from friend Simon.Plata. Thanks
  16. Another thing I noticed is that I can't get a red color at all !! The best I can get is something more like brown. I've tried to do the color adjustment but I never get close to the color red. I'm testing at CRT right now. I can never make it look like the emulator. See below both, Stella and real console running the same game at the same time at the same CRT screen.
  17. I added the 75R serie resistor as you recommended and the results (IN CRT) were GREAT!!!!! The vertical awful interferences has disappeared almost completely! The screen is now well more clean than before! The bright is still less than the desireble even with the trimmer setted ro 0K. After added 75R serie resistor, the trimmer acts a lot more!!!!!! In the Led TV I will able to test the device only later at night. I am at the lab now and the Led TV is at home. The serie Resistor changed a lot (to better) the results! Any Idea about the poor bright and dark colors? I am very sure that there are NO errors on the building the circuit. Checked up a lot! I need that the circuit work well in LED TV models. This console will be used only with LED TV. Thanks again friend!
  18. Thanks friend! I will do the test now!
  19. Again, thanks for answering friend. About the transistors, I used BC548C and BC558B. They are original ones (not Chinese crap). I have two other consoles with other mods that work VERY WELL both in CRT and in this same led tv that I tested here on this post. One of then is a very very simple thing and works very well. The other uses a CD4050 and transistors (the best I've seen so far till now) but it takes a lot of work to build so I was very interested in this one that you did because the idea looks great. Here are the schematics of the ones that I have used successfully so far in my both CRT and LED TV. About the cables I tested, both are resistance less than 1 ohm. I even tested your mod with the original 75 ohm RF cable as video cable and also with a good AV cable but the defects are identical in both. In CRT the image is much better but still far from desirable. At CRT, the Trimmer works but does very little. The colors are correct in both Led TV and CRT but are weak, ugly and dark and have vertical interferences. This same led TV that I used in the photos works well in the mods I send attached to this post. The 75 ohm resistor is exactly 75 ohms in the digital multimeter. Any idea? Thanks friend again.
  20. Hi friend. I did the mod and all ran ok on building the circuit but unfortunately the results was not good. About the transistors I used BC548 and BC558 instead 3904 and 3906 that are unusual ones here in Brazil. I attached pics to show you the image issues to ask if you could give me some idea. For the trimmer I tried from 0K to 10k but had no bright change. The image is dark and full of interferences and contours blurry. The console is in NTSC mode X200 (xtal) is 3.579545 MHZ I have great interest on this mod. Once more special thanks friend!
  21. Please tell me one more thing. Is it correct 10K for R9 (audio) ??? It appears too much high value to me. thanks again
  22. Wow!!! Thanks a lot again friend!! I will try it!!!
  23. Hi friend!!! Great post!! I will do that!! Very thanks for sharing with us!! Please tell me. What is the way to get the BEST trimmer adjust ?? Thanks again!!!
  24. I am asking because it would be a valued information to know if the issue appeared after or before the AV Mod. If the issue were before the av mode, the matter is in the console but If the issue appeared after the mod, the matter is in the AV mod.
  • Create New...