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DistantStar001

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Everything posted by DistantStar001

  1. I recently got what appears to be an early Vic-20 with a PET style keyboard, that has been modified with what turned out to be a reset button soldered to the motherboard, and bolted to the underside of the case. As far as I can tell, the computer boots up normally, with a little over 3 1/2 k in available RAM, and all the keys seem to work as war as I can test. However, the "Shift Lock" key does not stay down/lock when pressed. Which leads to my first question: Is that normal? I know on later keyboards it does, but this is an earlier model, so I'm so sure. My second question is more cosmetic. There is an odd dark discoloration near the front right foot (which is missing). I've tried Windex, rubbing alcohol, and baking soda with limited success. Any suggestions on how to remove it? Or do I just keep doing what I've been doing until it goes away? My third question is about an appropriate power supply. This is a two prong unit, so my jury-rigged C64 supply won't fit (even if it's safe and doesn't over-volt). I did find a simple cord that does fit the prongs. To test it, I had to cut off the outlet plug and strip the wires a bit, shoving one line into the barrel of a PSU from an Atari 1050, and wrapping the other end around the outside of that barrel. As you might have guessed this actually works, but it's hardly a long term solution. I don't want to permanently modify my Atari adaptor since I still have the drive that goes with it, unfortunately, all my searches for a proper replacement have turned up C64 style plugs, or been out of my price range. I could just rig up a barrel adaptor to the cord I've got, but I'd really like a dedicated unit, so I was wondering if anyone knew of a good place to find one? Fourth, I noticed while testing that my Vic got pretty warm. I don't think it's unusual. There's a pretty hefty heat-sinc on the board, and that's where the warmth is concentrated, but I was wondering if there was something more efficient, or should I be adding some fresh compound? My last question is the fun one. Now that I have a Vic-20, and I know that it works, what software and accessories should I be looking for? Game recommendations, peripherals, etc.
  2. Thank you so much! My drive is back, and I don't think I'm going to mess with it again unless there is a problem. Again, thank you!
  3. I have to run to work now, but I wanted to say thank you. I'll be testing your program after I get home. I have two formatted disks with DOS on them, so hopefully, that will work.
  4. Just updated my profile with my general location. Sorry, it took me so long to figure that out. Also, I cleaned the head with 99% alcohol and a q-tip since it always worked with my Apple //e.
  5. How do I get a copy of these disks? I don't have the means to interface the drive or the Atari with a modern computer to create one myself. As such, I've tried adjusting the drive blindly, but now it won't read anything and all I get is boot errors. I tried adjusting it counterclockwise to speed it up, only to see my drive eventually slow to a near stop. Then twisted it the other way and the drive sped up but gives me nothing but boot errors. Now it sounds more like an Atari drive, but it doesn't work. Can anyone tell me the value of the potentiometer at optimum? Maybe I can adjust this thing with a multimeter?
  6. Trial and error I'm afraid. No idea what the drive rpm is, and I don't think I have the software to tell me. And yes, I did clean the drive heads. How do I adjust the speed? That might explain why disks that work with my //e won't work on my Atari. Also, would the drive speed also explain why the drive doesn't work with Atariwriter? When the drive is on it gives me a red border around the boot screen and stays there. I tried turning the drive on after boot, but get an I/O error, same if I change the device number.
  7. I might have figured it out. The drive just formatted a double-sided double density disk successfully and wrote DOS files to it. Apparently, it just didn't like the disks I was using. Don't know why, my Apple II is fine with them, but as long as it works, I'm good. Now I just need a way to write software (other than Atari DOS) from the net with it.
  8. A while back I was given an Atari 800xl with a 1050 floppy drive. The drive had a bad 0 track sensor that had to be replaced, and internally at least one capacitor was replaced. Overall, the drive loads disks (at least 2 of the 3 that I have) and is rather quiet compared to the Youtube videos that I've seen of this model (the pitch is much lower, and sounds more like an Apple II drive than an Atari). The drive did format a disk once, but now every time that I attempt to format a disk, the drive seems to go through the motions of formatting, but ends with "ERROR- 173". I have tried both double sided double density and single sided single density disks with the same result. The disk I'm booting from is marked XE TERM DX 5076 and looks for an XM-301 modem upon boot. Upon failing to find the modem (not surprising since I don't have one), it boots to Atari DOS 2.5. I've used options I (format disk) and P (format single) with the same result. Any ideas?
  9. So like I said, replacing U26 made my computer boot normal for about a day, then it went to black. I opened it up, and the transistor at Q3 fell off. I replaced the transistor and ran a Dead Test and all I get is one flash on the screen indicating U12. So I replaced U12 and no change. Reading further in the Dead Test Manuel, I discovered that one flash could also mean either U9 or U21 as they're associated with data bits 1 and 0. I have replaced both chips, and still, all I get is one flash?? Any Ideas where this new fault is?
  10. Figured it out! Replaced 2 MOS ICs, and discovered that I had a 74LS374 where a 74LS373 should have been.
  11. So I just got a new c64 board, ASSY NO. 250425, that starts up with a mostly blue screen on startup, with a few garbage characters on the left side of the screen. The Diagnostic cart runs and performs all tests, but I have no idea what the results are since all the characters are garbled. However, it passes the Dead Test with flying colors and clear text? So far, I have eliminated the RAM, all 3 ROMs, CPU, both CIAs, the PLA, the SID, the VIC II, the clock 8701 as suspects. The board is pictured without ICs, but the ones I installed are good. Any ideas?
  12. So I have two Apple 3.5 inch Unidisk drives. One works fine, but the eject motor doesn't push the disc out all the way, but I can live with that. The other won't work at all. When I connect it to my //e, and inert a boot disc, the light flashes, then nothing. I've tracked the issue to the analog card in the drive, as when I swapped the drive itself between the two, the failure remained with the defective board. I've been poking at it with multimeters for months now with no idea what I'm looking for or luck in tracing the problem beyond the board. I really don't want to throw this thing out. Aside from the high cost of replacement, this was part of my grandfather's //e, so there's a lot of sentimental value as well. So if anyone has a schematic, or any advice on how to trace the fault, I would be very greatful.
  13. I don't know if this helps or not, but I had a similar issue with my CX-75. It had fallen apart, but after I tested it to be working, I glued it back together. For a while, it worked fine until it one day it didn't. I tried, everything to get it apart again, but couldn't. I tried stripping a q-tip of its cotton and cleaning the lens with some Windex, but no good came of it (no harm either). I was about to give up when I decided to give it one last try with a bigger screen. It works perfectly on the bigger screen. I guess mine's just near-sighted, but maybe this will help. If nothing else, I did manage to clean the lens.
  14. The keyboard controller (341-0035 342-0035) is the same between the Apples //e, //c, and ///, so it should work fine.
  15. OK, so minor update: I put a proper capacitor in C107 and checked the voltages. They all seem good, but I still get a black screen, even on the dead test. A friend loaned me a logic probe and suggested that I should check the clock oscillator, which I did. On my original, and the board that is missing its SID, I get activity on both sides, on the third board (the one that was missing C107) I get activity on the pin closest to C070, but the other is constantly low. My friend recommended replacing the oscillator, which I did, but there's been no effect, as I'm still getting the same readings. Also, on the same board, there is a small green ceramic capacitor bridging C041 and R042 at their nearest leads which isn't there on the other two boards. Does anyone know why that might be there? And should I remove it?
  16. I was recently given a Beige desktop G3, and so far it works great, but then I've only had it for less than a week. So what exactly makes them a pain? Just curious as to what I'm in for? Also, I almost completely concur on the SE, except the "fast" part. I have three of them (only one with an accelerator card), the other two (much like my Mac Plus) are painfully slow. Still, they do look great and I love playing with them just the same. :-)
  17. The //e card and software environment isn't an emulator, it's a user interface that allows you to interact with additional hardware. The difference being that the //e card is a near full Apple II complete with an integrated 65c02 processor minus a hand full of functions (like RAM and ports) that the Macintosh logic board provides. The software simply allows you to interact with it. In essence, installing a //e card is literally installing a full Apple //e into your Macintosh. By contrast, an emulator simulates all that hardware in software as well as the user interface. Sadly, 68k Macs aren't powerful enough to do that. Although interestingly, PowerPC Macs actually do run an emulator in the background in order to run 68k compatible software. The truth is that the //e card was never really meant to provide a true Apple II experience. Rather, it was meant to help //e users to migrate over to the Macintosh platform, That said, the //e card is remarkably compatible with most Apple II software, so long as it's 65c02 compatible. Some older software designed for the 6502 won't work (this includes most but not all versions of Centipede that I've found), and the color/black and white options can be a little wonky with some text-based programs. Bank Street Writer, for instance, won't display legibly in black and white mode, and the artifact color makes the text unreadable in color mode. AppleWorks, on the other hand, works just fine in both. The biggest annoyance for me (in use) is the "Reset" key. On an Apple //e, holding "Control-Reset" goes to Basic prompt, and "Control-Command/Open Apple-Reset" reboots the computer. On an LC III, the "Reset" key is for a soft reboot. If in //e mode, you hit the "Reset" without hitting the "Control" key at the same time, your whole Macintosh will reboot instead (not just the //e). Since resetting a //e is the principle way to switch between programs without turning it completely off and on again, one can see the problem. Another issue is cost. As I said, this isn't an emulator, so you will need to buy some additional hardware to make this work. At minimum, you'll need a 5.25 in floppy drive (which isn't too expensive) and disks, plus the Y-cable to connect it (those things were going for around $90 alone the last I checked). Add the actual //e card (another $100-$200), the LC III (probably $100 plus), a monitor, keyboard, mouse, and price wise, you're well past the cost of an actual //e that would run more software.
  18. You can see some of the white marks in this, but some were bent over on the other side. Also, I removed the chipped one and cleared the holes at C107.
  19. DistantStar001

    Commodore Rebrick

  20. Yes, I've swapped all three VICs between all three boards. On the first new board, all three booted to the dead test and gave the same result. For the most part, both of the new boards seem to be in equally good physical condition, but new board #2 is missing C-107. The whole board appears to have been recapped, but unlike the other boards, there's nothing in that spot. So maybe that's the problem? It is literally because of the number of capacitors that show signs of damage that has me wondering. About 12 of them have white marks, and then there's the one with a chip.
  21. Update: I removed, and socketed all the Ram, but managed to damage at least 3 traces in the process. I tried patching them with wire, but it didn't help (the best I got was flashing on the dead test, and occasionally gibberish on the diagnostic cart), so I decided to buy two new boards to see if I could use them to figure out what's wrong with my first. The first new board is missing its SID, but boots to the dead test. The color RAM reports bad, which isn't a surprise given the funky colors of the text. Also U9, U21, and U23 report bad, after that it just stops. I tried swapping the VIC since it's the only chip socketed on the board but got the same result. The second new board is socketed on all major chips but was missing its PLA. All I get is a black screen even with a known good PLA installed. There's no flashing on the dead test, and swapping the VIC didn't help. Physically, the board has some problems. A number of the ceramic capacitors have odd white marks on them, and at least one is badly chipped (I think that's a large part of its problems). Also, when I got it, the power switch was bridged to be permanently on. I fixed the switch, and it seems to function normally. All the boards in question are 250407s, with the new ones being REV.B, as opposed to my original, which is REV.A. Any ideas on how I can get any one of these to work?
  22. That's alright, thanks for looking. I'll keep poking at it, you never know, I might get lucky.
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