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eizner23

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About eizner23

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    programming, audio repair

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  1. The blurring was also present on the original AV mod i tried, just not as bad- so I dont think its the cause of blurring. I am reading about the UAV and it has circuitry to align the 4 luminescence signals into a perfect pixel edge, perhaps that is what I am lacking on this VCS model. At this point I may chalk this up as a learning experience and integrate the UAV into the unit. It was a fun experiment anyways.
  2. Thank you for the kind help Voxel during this saga. I analyzed video output on my scope of video out rca and before it enters the amplifier I assembled (pin 4). Waveforms look the same on the scope. I'm curious if we can see any anomalies here. Its Barnstormer on the intro screen when you first turn the game on, no motion. I may see what the output looks like on another unit out of curiosity. This is the blurring I'm seeing, notice the yellow fence posts spilling over. Not much solder was done to the board to cause any blobbing really. I've been reading the video troubleshooting in atari field service guide for clues I will post if I find anything out.
  3. Thank you for the further advice. I got rid of the wiring I had in exchange for shielded cabling for a cnc machine. I followed your instructions by soldering the shield (bare wire) to ground on both ends. Unfortunately I am confronted with the same video issue.
  4. There is no wiring for video between the VCS and av board, I'm using header pins soldered to the two. Not sure where I can salvage shielded cable but I'll look around. Could I temporarily tack the video rca using a tiny bit of wire right next to the av board to determine if this is the cause?
  5. I am receiving the same results on a different LCD TV and with different cables and power strip. Even tried a 75ohm cable. There isn't really anything else plugged in the room the atari is residing to cause interference. Looking at schematic I'm curious if c215 is still neccessary?
  6. I found an old heavy 9v 1A linksys wall adapter that is working fine, the power issue is sorted out thanks everyone for the help. Now I am sorting out this blur on right side of graphics. I read maybe due to over driving video signal. Adjusting the gain pot on the video amplifier board doesnt help any. The problem got worse going from one transistor to two transistor composite board. Is it true these light 4 switchers are finicky with composite mods?
  7. I had an identical issue with vertically scrolling fuzziness on my light 4 switch. I was using a $10 Retro2600 switching power adapter. Problem surfaced after AV mod. After reading this helpful thread I tried an old heavy Linksys wall-wart rated at 9v 1A, under no load it measured 16VDC. The new 7805 regulator with 35v max input handled power adapter fine while staying under 110F. Problem solved. The Retro2600 does seem to be OK on other unmodified 2600 units.
  8. And thank you for posting useful info! Must appreciated. I will set my quest to find an optimal power adapter, and ordered 3.5mm male mono Jack's just in case. I'll hold off until the power source is resolved.
  9. Thank you I bought a few from mouser at premium cost!
  10. The power supply I was using is the Retro2600, a super light, switching PS with 9V output at 500mA. As alternative I used my bench PS set to 14VDC and the wavy vertical scroll issue went away. I read original atari PS puts out 14v. Is there a better replacement solution? Maybe I can make my own using old laptop supply for now. Curious what the out current was with original. The only issue remaining is the gfx terribly blurring to the right. Confirmed 5.08v getting to the composite board.
  11. I tried the av mod from the future was 8 bit site. It's circuit is little different, the circuit I was using had no resistors on emitter. I gave it a shot and couldn't get any video, I tried two different boards! Old one still worked. More digging I found a circuit using two transistors, the author described the same issues I had with the one transistor circuit. post 13 here Doubled checked work and tossed it in. Identical results to my first board, and the graphics became more blurry on the right edges of graphics. The wavy band wasnt as prevelant but still there. I removed more parts from the old RF, I x'ed parts I took out below. Put in new 2200uf cap. Reseated 2 of 3 chips, not the one under cartridge port yet. Wrapped the output wires once in a ferrite core. Nothing changed. Ha! I'm going to probe around with my scope, check parts upstream, see if I'm getting 5v to the new board. My testing of new board was done without the shield over the chips.
  12. Thank you gentleman the ground issues makes sense. I read the first link in post #3 and that seems to be a better solution, and his initial issues match my issues. I'm going to redo my work and use the ground plane as advised. I'll let you know if the results are work out.
  13. I used this 5v 1.5a 7805 regulator on left and measure constant 5.09 under load. I captured an image of the issue Maybe try a new 2200uf filter cap? There is a green mylar near it too.
  14. I have LM340T 7805 on hand, 5v 1.5a output, I'll give that a shot. ...And it didnt help, made the banding a little more prevelant. It's like two wavy RGB patterns slowly moving up vertically. Tried giggling and touching the new wires that were introduced. Reflowing the filter cap. Didnt notice a difference.
  15. Another note I have an led hooked up to the regulator and that doesnt even light up during the cold start issue. I'll try to squirt with freeze spray when it does work, maybe will prove faulty regulator.
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