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Sherry Haibara

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  1. It could also be a bad floppy drive, usually a dead chip in the drive itself doesn't prevent it from showing some sort of correct behavior; for instance, if one of the socketed chips inside the drive itself is bad, you may end up with a drive that is normally able to read but not to write any content. You might want to check them as well! Do you have any way to test the drive separately (i.e. another machine)? EDIT: I actually read now that after using ctrl-reset, the typed characters don't show up on the display, this seems to point to some issue with the Apple II itself indeed. You might st
  2. Yes, mine did exactly the same thing. A couple of things you can easily troubleshoot when you get it: 1) Check that the motor spins freely if you move it with your finger. When I got mine, it had become stuck just a little bit, so I was able to turn it manually but it wouldn't spin up on its own. As a precautionary measure, you can use some WD-40 or other lubricants directly on the motor, that should do the trick. 2) If it still doesn't work (or if the motor was fine), check the laser lens. It tends to get weaker with age, cleaning it gently with cotton swabs or cloth (like the one used for
  3. Hi all, long time no see! I always felt I should share my personal collection with you, but I could never find the time to take proper pictures of it. Well, as a matter of fact I still haven't, but I figured I could just start the topic and progressively add more items! So I'd like to start with today's find, an almost mint Macintosh SE, with very few scratches and almost no yellowing! I actually got this one for free from a guy that was essentially trying to have it gone as soon as possible, so it could have easily gone wasted in the trash. He was probably an architect at the time, because
  4. Hi all! I kinda forgot about this topic, but recently Ferrix was able to figure out the issue. It turns out it really was a matter of SCR, for some reason the modern replacement just didn't work in my particular board although it worked perfectly in a similar board. We actually were able to source an original E0102 and with that the Macintosh works perfectly! It's still beyond me why all other supposedly equivalent components didn't work, but alas, the only thing that actually matters is that it's now working fine!
  5. SCR has now been replaced! We've got some progress, but we're still in need of some help. At the moment, we are able to get a "stable" raster (albeit it's somewhat shaking in the corners) by supplying exactly 63V to the board through a variac. Any more or less and the system enters an endless flubbing loop. This seems to suggest that something is going wrong in the power regulation circuit. To be fair, caps haven't been replaced yet, but we're not sure whether they may have something to do with this or not. Flyback has been removed for testing, and the board exhibits the same behavior even
  6. Hi all, Ferrix and I finally started the long troubleshooting process to bring this poor guy back in shape again. So far we are focusing on the logic board, which is probably the most problematic. As a first step, we have confirmed that the installed ram is effectively summing up to 128kb and also seems to be of the correct type (though I don't remember the chip number at the moment). We have undone the modification that allowed ram expansion, using a working 128kb logic board as a reference to avoid cutting factory mods. We have tested the board with a known to be working AB, and t
  7. Just bought myself one of these - late 2007 santa rosa model, for 30 bucks! Cosmetically in great condition - it was used very very little, the battery has less than 200 cycles and the keys are practically mint. It doesn't even have the classical cracks on the top case that almost all machines of that era had. Only "little" problem is, the logic board has prematurely died. I'm waiting for a spare compatible logic board to arrive from the states in the next couple of weeks to bring this little boy back in shape, and possibly upgrade the HDD to an SSD too - notably, it has been upgraded at so
  8. Wow, you never stop learning... I didn't know such a thing even existed! I guess I always thought monitors worked like magic (: So as far as the video goes, nothing to worry about. I'll have a full recap of the board and keep you updated!
  9. Hi everybody! While I still haven't had time to fix my 128k, I managed to grab a Color Classic the other day. The opportunity was too good to pass up, because these things don't show up that often in Italy. To the point: the machine was sold as non-working because the owner didn't actually know how to turn it on. As soon as it arrived, I plugged in the keyboard and I managed to turn it on. However, it has a few issues (unsurprisingly). The most critical one is this: when I turn it on, the screen becomes white (a solid white/grey color) and just sits there. It doesn't chime, though I believ
  10. They still teach us the 68k assembly and microcode at my university - from an architectural point of view, it's an incredibly elegant design. Much more convenient to use than the cumbersome syntax of the x86 family, and it provides a great deal of extra flexibility too. My favorite feature is probably the (almost) complete orthogonality of the instruction set with respect to the available addressing modes, which is simply *so* cool and convenient, while the x86 uses all kinds of tricks and strange assumptions about which registers you can use with which instructions and so on.
  11. Gorgonops, I'm equally disappointed as well. If at least the memory upgrade had been still in place, it would have been an interesting modification to have. Sadly, it could be hard to restore it; it seems most of it is still in place, but a couple of wires have already been cut here and there, so it would be a matter of reverse engineering it, which is not something I'm expert on. Sure, if somebody here is able to understand what is missing and what should be connected to what, then it could be feasible after all. I wonder if it would still work with the full modification in place and only 128
  12. Yep, the original seller (the american one) said that a certain point this board was upgraded to support 1MB of RAM, which basically converted this thing into a Macintosh Plus minus the missing SCSI port. Since then, the chips have been reverted to the stock ones, with the exception of not being Apple branded; however I guess they "forgot" to remove at least part of the modification... I'm wondering if it would be just fine to remove all those cables? I honestly have no idea of what crazy magic they're doing to enable the machine recognize more RAM, but I recall that at least a few "ram upgr
  13. Hello everybody, I'm back again with another conquest of mine! This time luck has brought me nothing less than a Macintosh 128k, which I obtained from a guy in Italy. Now, the story of this poor guy is an unhappy one, unfortunately. The guy who sold me this one said it was in working order and that he had found it in the garage of a friend, but of course that wasn't true - in fact, I discovered that he has bought this machine more or less a month ago from an american guy on eBay with defects. So now I have an open dispute with him to try and get back some of the money, but meanwhile I'm tryin
  14. They *should* be fine. Q3 seems to be actually the same component (BU406), while the replacement you found for CR1 is an upgrade of the original component, with response time of 150 ns instead of the original 200 ns and similar current/voltage specs. If you want to go with a component which is as close as possible to the original one, digikey is still selling the GI824 (which is the original CR1), or you could buy this one which is even faster. As others have already told you, try replacing Q3, CR1 and the flyback first and go from there: be prepared to what could be a rather long trial &
  15. Just be careful while cleaning the floppy drive, it's easy to bend the heads and make the whole thing a nice but useless doorstop. Killed a couple this way!
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