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Everything posted by sideburn

  1. This is awesome. I’ve seen all the pofoduino videos on YouTube and subscribed to the channel. What’s the current state of this project?! Where can I find the PCB files, schematics, software etc that I would need to build one? I have a portfolio on the way with a parallel interface and want to dive right into this so I can transfer files to it and send data out to other devices with the NRF 24! Im just hoping this thread and project is still active! If I can’t buy one ready to go or a kit, I am ready to build one! thanks for any info…
  2. Hey guys, I’ve got an odd issue here with a like new 1050 drive. It powers up perfectly. Does the initial drive stepper motor sync. I/o to computer is good. But when I power up the computer the drive spins up and just beeps every few seconds like the disk is bad. but if I wait about 15 minutes all is good and the drive works perfectly. I just re-capped everything and no change. Any ideas? I tried blasting areas with cold air but nothing suspicious yet. the heat sink is getting pretty warm. Not sure if that’s normal and I’m getting 10v a/c off the power supply.
  3. Hey all, So my newly repaired and re-capped vertex has one final issue. Some games, especially demos with rotating shapes have broken lines. Using the Test Cart, every test looks perfect EXCEPT the 3d box in the Deflection test. Any ideas on the case and/or how to fix this? photos attached:
  4. All fixed! The journey is over 😂 at least for now… thanks for the help
  5. It’s pin 11 on ic305! I poked around with my finger and it started working. It’s a bad socket. I’m swapping it out now.
  6. I just swapped out the sound chip. No fox on X but the sound is fixed and the game starts like it should. Could it be one the R335 POT?
  7. I'm going to swap out the sound chip. I think it might be causing 304 to block the x output. The fact that i have to muck with the player 2 controller to get a game to start is a clue and the horrible sound output. I dont understand why the 4 analog joystick pots are going to the CD4052 and IC304 in the first place though. What is the comparator doing there?
  8. Great, always as good feeling when the things finally come up alive again!
  9. Looks like my previous reply through email didn’t go through but this is what I said: Oh my gosh thank you so much. You can definitely read one better than I can! I don’t know how the mux and switchers work so it was boggling my mind how the x signal is working! I was thinking the 4052 had nothing to do with X and it was controlled by the 1408 d/a converter! 😆 🤦‍♂️ and I here’s what I am getting off the scope: 305 pin 9 has a strong signal 305 pin 10 has a weak signal but when I turn the volts/div up I can see data 305 pin 11 has no signal 303 pin 14 has a weak signal as well but I can see data with higher voltage/div 303 pin 13 - none With 303 removed from the board: 303 pin 14 - strong signal 303 pin 13 - strong signal 303 pin 9 - strong 305 pin 9 strong
  10. Do you think ic208, the sound / joystick input controller could have anything to do with it? The sound is wonky and the game won’t start unless I pull pin 7 on that chip low which is not normal so I think that chip is going bad. Could not somehow be affecting the switcher for x?!
  11. Hey all, I’ve been repairing this old board for a while now and I am down to the last issue and I’m currently stumped! my x axis signal is extremely weak and I only a single pixel image down the center. I’ve replaced most chips and socketed them. Looks like I’m getting a good signal on ic304 pin 1, and ic302 pin 13 looks good. i just don’t quite understand how the system controls x and y or switches control between them. as you can hear in the video clip here, the sounds is wonky and a game won’t start without hitting a button on the player 2 controller so i think the ay sound chip is back but I don’t think that would be related to the video collapsing issue would it? I’ve recapped the board and every chip you see that’s socketed is new. New sockets new chips.
  12. Did you check all the chips for continuity. Put one lead on the pins on the chip and then the other lead on the solder connection on the other side of the board. The problem with my black screen issue was ram and bad connections with the chip because the stock sockets are pretty crappy.
  13. Ahh didn’t know the names. Dual wipe installed. Still going strong
  14. I think we are good to go now! I cleaned all the pins on the ROM, swapped out the socket, dexoxited al the other sockets, rinsed the board in isopropyl, and blew it dry with an air gun. You can't even tell I swapped out the socket
  15. I think I got it. It's either the ROM or the socket. I noticed the ROM tests are failing (red bars) when it starts acting up. I cleaned the pins and re-seated it but at an angle in the socket and so far so good. ** just swapped out the socket and i noticed the originals are those crappy ones with the metal tabs only on the insides so it doesn't grab the chip pins from both sides
  16. I dont think its the Ram the ram tests are passing while the screen is going bonkers and i swapped out the new ram with the old and back. Yeah I reseated the chips many times and inspected the board. Its clean. New... I found an old 800xl in storage maybe the chips are socketed.. Sometimes when i power up it goes straight into the ram test. When it powers up my Atarimax and unocart work flawlessly. The only failures are the self test pages go whacky on the screen and it occasionally booting directly into the self test. if it doesn't it works perfectly consistently.
  17. Well I Deoxited every chip on the board. The problem is totally random. comes and goes so I don't think it is the shield (its off for now until I sort it out) nor a bad connection. it has a life of its own so I think its a bad chip. I need to get some canned air and freeze the chips and see if that affects anything. ** I found another clue... if I let a test run for a while like the memory test, the flickering gets worse and worse over time like the sprites are flying all over the place on the screen and then when i force the screen to redraw by returning to the main menu it draws the screen perfectly and then starts messing up again. This might explain why games are working ok because the screen is redrawing a lot.
  18. So the good news: The new cable got here today and it is 1,000 times better. Now the picture is how I remember it being. And the bad news: Today is also the day the 800xl decided to start acting up again... goes directly into self test and the screen is bonkers (but looks much better with the new cable! lol)... Time to get the Deoxit out...
  19. Yeah kapton would be best for that I think. If it starts acting up again I’ll take it apart again, inspect the shielding, kapton insulate, and Deoxit the sockets. I’ve always been using my 130xe and left this 800xl in the box since it’s it such NOS condition but now I think I’m going to start using it instead. I forgot how much nicer they are.
  20. I have a feeling that might have been what happened after I replaced the ram and it still wasn’t working. I had the bottom sheiks under the board just loose.
  21. I agree. I bet it was only the ram. Yeah, I may pull it back apart and spray all the sockets. I’ve already got plenty of Deoxit. I love that stuff! I should have thought of that when I was re-seating all the chips. Yes, still issues with the 130xe convergence but it’s looking the 800xl video is about the same so I’m leaning towards it being the cable. I hooked RF to the 800xl and it looked much better. Still need to try that on the 130xe. Still got two more machines to fix. An Amiga 2000 that I don’t know what the heck happened to it, but it had major issues. Bad ram, blown Agnus and CIA chips, corroded battery & leakage, and more. I’ve finally got that working except for the hard drive. The disk activates and then solid HD activity LED. A Vectrex with a board that suffered bad corrosion. It’s now got a clock but that’s about it. Also an Apple ][ plus with bad ram that I just fixed. All of these have been in storage for a few years. In the same location. It’s interesting that all of them have / had bad ram and were all in working order before I boxed them up back then… I should probably get rid of a bunch of this stuff so I’ll have fewer broken things to fix every day and be forced to get some real work done! 😂 *The Ataris ain’t goin nowhere though. I still have all my floppies and programs from when I was 13 for those puppies.
  22. That’s what I did. I think I’m good to go. Looks like it might have been a bad connection with the rom and a couple bad ram chips. thanks for the help everyone.
  23. I think I got it. I think the shield thing was just a coincidence. I re-seated the ROMs and so far so good. Time will tell… I’d ditch the shields but this one is brand new. Rather keep it in mint / stock condition.
  24. OK the plot thickens... All the sudden it got really bad and powers up straight into self test and the screen is going nuts... I take the whole thing apart again, remove the metal shield of the top and the bottom and set the board down on the workbench, power it up and its working flawlessly... self test page is nice and clean and passing all tests.. What gives! when i pu the thing back together it goes whacko on me.. Tempted to not put the damn shield on. what a PITA!
  25. OK I got that RAM and this was weird. I swapped all 8 out and no change, black screen. I then swapped the only socketed chip I had in mu 130XE, the GTIA and no change.. I then try powering up again and boom its working! So I'm not sure if maybe the metal shield on the bottom was shifted and shorting something or what but it's working now. I then swapped the original rams one chip at a time and found two bad rams. The only issue now is the self test pages start going bonkers on the display but they are working properly. Only the display starts jittering around like crazy. Everything else works perfectly, I put my UNO cart in and ran a bunch of games and demos and they all work fine. So I am not sure why the Self Test screen is whacky...
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