Jump to content

spicyjack

Members
  • Content Count

    16
  • Joined

  • Last visited

Community Reputation

12 Good

About spicyjack

  • Rank
    Space Invader

Profile Information

  • Location
    San Diego, CA

Recent Profile Visitors

1,430 profile views
  1. I actually have this open in another browser tab, but I haven't made it all the way through the thread yet. Thanks for posting though!
  2. I did what the article said; I didn't realize that you had done a 2nd version. I still have everything in my garage if I wanted to re-install it. I powered it on it after I put it together and it booted fine, I just didn't get a photo of the right chip in the right socket, and guessed.
  3. When the "QuarterMeg XL" article by @ClausB came out in the September 1985 issue of BYTE, I had to try it on my K-Mart special Atari 800XL. For reference, here's the original BYTE magazine article: Quarter_MEG_ATARI_800XL_256kB_RAM.pdf I bought the chips mail order from a place in San Jose, bought the perf board and chip sockets from my local Radio Shack, and threw it together. After the upgrade, I explained to one of my friends what I had done, and he asked me to do the same upgrade to his 800XL. Years later, he got out of 8-bit Ataris, and he gave me all of the old hardware that he hadn't sold on Ebay. This is his 800XL which I had upgraded about 35 years ago. I remembered that I had did this upgrade to my 800XL, but I had forgotten that I did the same upgrade to his 800XL. I recently took this machine apart to document things (was the board socketed or not, how much corrosion was there on the RFI shields, etc.), and I "found" this upgrade attached to it. SURPRISE! The thing was, I used telephone hookup wire for most of my electronic projects at the time, since I had a bunch of it sitting around (my dad worked for the phone company), so I had a sneaking feeling that I had done this upgrade, but I wasn't sure. For about an hour or two, I was pretty convinced that this was my original 800XL that I somehow ended up with again as a craigslist/Ebay purchase. It was pretty spooky. But, I thought about it some more, and realized what the deal was; this was my friend's machine, and I did this mod on his 800XL after I did the mod on my 800XL. Thanks to @ClausB, his instructions were solid, and the trick about using half of an IC socket to so you don't have to solder directly onto the PIA was great, it was a clean install which uninstalled very quickly, I just had to cut one wire that I had soldered on to the board, "above" the row of RAM chips. So here you go, I'm going to remove this QuarterMeg XL upgrade from ~35 years ago. I pulled off the keyboard, and the RFI shield was still in place. The discoloration of the RFI shield most likely comes from the part of San Diego where this machine was used and stored, it's a few miles from the Pacific Ocean. I pulled the RFI shield off, and WHOA! what's that there? Close up of the perf board with the RAM refresh chips, and the ribbon cable where it plugs in to the board The pins on the PIA bent up, and the wires soldered to half of an IC socket, in order to make it easy to attach/unattach as needed. You can see the piece of electrical tape that covered the tops of the pins to protect from shorting it out against the RFI shield Starting the uninstall Close-up of the perf board, with the electrical tape attached to the bottom And here's the board post-uninstall. The 74LS153N got resocketed from the perf board back into the 800XL board. I have a chip pin straightener, so I was able to get the PIA pins back to their "normal" angle pretty easily. The machine boots fine with the 256KB RAM chips still installed, only the first 64KB would be used at this point Thanks for reading, feel free to ask me any questions.
  4. Makes it a little bit harder to see what to hit, actually, the bright red stripes are distracting. Here's the bag after I had had my way with it.
  5. I don't think that would work, see the pictures above. The power supply was filled from the "bottom" upwards (turned over and filled from the bottom, then the bottom was epoxied on), which means it would suck to try and get the epoxy out as one piece so that the shell is still usable and not deformed. I've seen other mentions of using acid to dissolve the epoxy, it kind of sounds appealing in a curiosity way (what's inside that epoxy, eh?), but I definitely don't want to go there, I lack the experience to properly handle and dispose of any kind of acid beyond household chemicals.
  6. I took some more pictures of the case post-teardown, and the only reason the resin "brick" came loose was because I applied force to it. You can sort of "fake it" putting it back together once you get it apart, but it won't pass close inspection.
  7. Okay, let's get started. First, this work is licensed by: Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0) Second, note that safety equipment was worn during this whole little episode... safety glasses, auto repair gloves, and flip-flops, because Southern California! Third, I've posted the full-sized pictures on Imgur, they're a bit large to post here. Let's get started! Here we have our "donor" Ingot/Boat Anchor power supply. The smashing tools... #1, "Big Sledgy" and #2, it's little brother, Little Sledgy. The donor Ingot came packaged in a zip-lock bag from the sender, but that bag didn't hold up that well to the punishment. During the COVID-19 pandemic, all of the stores in my area started using really thick plastic bags, which are perfect for catching flying debris from sledgehammer blows... highly recommended to "bag" your prey if you're going to go off on a smashing adventure of your own. After this little episode, reflecting back, I think the best way to crack this sucker open is to hit it on the top corners first at the ends with cords, then flip it on it's side and then hit the edge that sticks up the highest. The goal is to pop the plastic off without doing too much damage to the contents. If your goal is "surgical disassembly", I found that using finesse and the weight of the hammer with gravity worked well. If you just want to destroy it, wailing on it works too. Transformer peeking out. Starting to see some of the resin inside. The transformer and the voltage regulator/power smoothing board. Another shot. The purpose of the aluminum piece will become apparent in a sec. Good shot of the resin that the manufacturers of this power supply used. I like how it looks like flakes of granite when you bang on it a bit. Ah-ha. Voltage regulator. Better shot of the voltage regulator. What are you hiding? A fuse and diode. A capacitor and some resistors. Better shot of the capacitor. I went a bit more gently around the capacitor. Chton 4700microfarad capacitor, 16 volts. Where the capacitor was placed on the power supply board. More regulator board Closeup of the fuse and diode. Another shot of the diode. Fuse and location for the capacitor. I like how the markings of the capacitor were picked up by the resin. Again, this resin looks like granite rock when broken apart. Okay, that's it. I hope you enjoyed my little teardown.
  8. I have the pictures from the "teardown" ready to go, but I lack the energy today to post them in a way that does them justice (I cooked breakfast and dinner, and beat up on the yard in the afternoon). Come back tomorrow, and they'll be here. Thanks!
  9. *cough* An Ebay package showed up for me last week, and inside it was an 800XL with an Ingot (my 2nd Ingot). I had a little bit of free time last weekend, and did a "teardown" on that Ingot... with 5lb and 2lb sledgehammers. Would it be worth it to quasi-hijack this thread with all of the pictures of Ingot destruction, or should I start a new thread with them? If you've never seen one opened up, it's kind of cool looking inside. Edit: added a sample of "the goods".
  10. Listed 5 days ago and located in Sunnyvale, anyone with $10k (US Dollars) burning a hole in their pocket can pick it up. https://sfbay.craigslist.org/sby/vgm/d/sunnyvale-super-rare-atari-cx-2000/7144866997.html The attached image was snarfed from the Craigslist posting. (Edit: added currency designation)
×
×
  • Create New...