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johnklos

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About johnklos

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  1. I've always heard that the baking soda helps with anything acidic, but the vinegar is to remove any minerals after washing and cleaning. So yes, those, then distilled water with no minerals seems to make sense based on what I've been told. What's IPA?
  2. You're not talking about beer, are you? I was given a severely corroded LC II motherboard which I thought might never run again. Since the capacitor goo ate away some of the traces, some came up a bit simply from cutting the leads. I washed the board with soap and water, with baking soda to neutralize any acid and to act as a surfactant, then vinegar to remove any minerals, then with distilled water to remove any vinegar. I also used toothpaste and a toothbrush to physically remove gunk and corrosion. I then repaired all traces, installed new caps and tried it out. Guess what? In spite of the poor state, it works! It really all depends. If you have nothing to lose because a board doesn't work, then do whatever you have to do to clean it. But being aware of how minerals might affect things. If you have high mineral content in your area, then maybe dishwashing isn't a hot idea. If you have water softening or very low mineral content, then why not? For removing caps, sometimes you can't help screwing things up no matter how hard you try. I have those precise needle nose side cutters which are meant for this very thing, but if the pads are literally floating on goo and corrosion, you just have to make due.
  3. johnklos

    Sonnet Quaddoubler project

    It seems the NeXT forum is available again: http://www.nextcomputers.org/forums/index.php?topic=56.0
  4. That separate thread is gone. You can't just post a link to a Windows executable without any description and not expect people to be a bit suspicious. Also, it appears to have a ROM file, which is not allowed here.
  5. johnklos

    68K (no Mac) Designs OK?

    I had a Sinclair QL, which was quite a fun little machine based on the m68008. Of course, there's the Atari ST, the Japanese LUNA machines, Sony's NET WORK STATION workstations, NeXT, of course, Sharp's X68000/X68030 series, Hewlett Packard's 9000 Series 300 and 400 workstations, Suns, Apollos, plus lots of VME boards, including multiprocessor systems. Let's not forget the Tandy TRS-80 Model 16 and Tandy 6000! There were plenty of others I'm not remembering right now. I'd love to build a simple system some time using either the 22 address bit version of the m68008, or perhaps an m68030 since it can size its bus to 8 or 16 bits, plus it can run Unix / BSD without extra chips because it has an MMU. One day!
  6. johnklos

    Full 68040 for Quadra 605

    Is it a 5 volt or 12 volt fan? I forget. Noctua has 5 volt and 12 volt available at that size: https://smile.amazon.com/Noctua-NF-A6x25-5V-Computer/dp/B01K4HRLRI/ https://smile.amazon.com/Noctua-60x25mm-Blades-Bearing-Premium/dp/B009NQMESS/
  7. johnklos

    Full 68040 for Quadra 605

    Hey, Fernando! Yes, heat is an issue if you're running at 40 MHz, but if you have an L88M or K63H mask, it's already cool enough. For an early mask (any XC part) at 33 MHz, you need a heat sink or you need to make sure the fan in the case works, and for an early mask at 40 MHz, you really need both the heat sink and fan in order to make sure the CPU doesn't overheat. Most '040 sockets have clip mounts on the sides, and the heat sinks and clips that one can get from Quadra 650 / Quadra 800 machines fit fine inside of a Q605 / LC475 case. Or, when the socket doesn't have clip mounts, or when you don't have the right clip and heat sink, you can always use something like Arctic Alumina thermal adhesive epoxy to hold on a proper heat sink. It's pretty permanent (I've never tried to get a heat sink off after adhering it), but works well.
  8. johnklos

    Apple Set Top Box

    If I remember correctly, AV machines require an FPU. Try swapping in a full m68040.
  9. johnklos

    RaSCSI Development Thread

    That'd be called a SCSI card You can give Basilisk a file device, or you can give it direct access to a block device, so all you'd need is a real SCSI card plugged in to the SCSI device of your choice.
  10. johnklos

    Original Hackintoshy Thing

    http://www.maccaps.com/MacCaps/Repair_books_files/Macintosh Repair and Upgrade Secrets.pdf Page 168 and on describe the adapter. It's just a 74LS14, which is just an inverter with a Schmitt trigger, which just cleans up the signal so superfluous changes aren't reflected on the output. The board in the first picture has a 74F253, which may be used to decode address bits or something like that for... a hard drive LED? It'd seem strange to have so much circuitry for just that, but I don't see any other hardware in there that would make use of this...
  11. johnklos

    Full 68040 for Quadra 605

    You know, one of my Q605 motherboards has a MC88916DW80. When I find that specific motherboard, I'll try that out. I bought, I think, half a dozen MC88916DW80 and only used one, so this would be good to know. I find it interesting that because of the amount of time spent using the bus, my QuadDoubled machines running at 50 MHz with a 25 MHz memory bus are, for many uses, slower than a 40 MHz overclocked Q605. Good, solid, true 40 MHz overclocks would be very nice, particularly when I start to build my Q605 cluster
  12. johnklos

    Full 68040 for Quadra 605

    If I remember correctly, stuff (no idea what) won't run at the full 40 MHz. Don't know if memory is too slow, or if some of the peripheral chips won't run at 40 MHz, or what. So the idea is to run the motherboard at 33 MHz, then remove a surface mount resistor to disconnect a clock going to the CPU's clock generator (the MC88920), then wire the output of the 20 MHz oscillator to the pad which leads to the CPU's clock generator. It's outlined here: Quadra 605 overclock to 40 MHz using crystal oscillator I've done this on many Q605 boards, and they typically don't run at 40 MHz, according to Clockometer, but they run close - usually around 38 MHz. I don't know how this works this way, but it does
  13. johnklos

    Full 68040 for Quadra 605

    BTW - all m68040s, with the only possible exception being 1990 engineering samples, were made from the same batches that made 40 MHz parts, so pretty much all of them can run at 40 MHz with good cooling, and all of them can certainly run with no issues at 33 MHz with a heat sink. Running a Quadra 605 or Performa 475 system at 40 MHz, though, requires a 20 MHz crystal oscillator and a wee bit more soldering.
  14. johnklos

    Quadra 650 & 800 Logic board differences

    There are no speed or component differences between Quadra 650 and Quadra 800 models. The Centris 650, though, ran at 25 MHz, and some came with LC040 FPU-less CPUs and without motherboard ethernet.
  15. johnklos

    Full 68040 for Quadra 605

    Most m68040 CPUs in Macs are XC because Motorola took so darned long to "qualify" the '040 to make an official MC part: Official MC mask announcement Original XC68040s (D43B, D50D, D98D, E31F) run hot and are .8um masks, but will run fine at 33 MHz with a heat sink. The E26A is an XC part with a .65um mask, which might be a little cooler. Starting with the E42K mask, they are fully qualified MC68040 parts with .65um masks. Then K63H reduced the mask to .57um. Finally, the latest / last version is the L88M, which is also .57um, but runs cooler than the K63H according to some sources. This version is usually made by Freescale and has their logo in place of the Motorola M. Some eBay sellers scrub the markings off of older m68040s and print newer markings on them to sell them for more money. Unlike the m68060 which has bits in a status register which identify clearly the revision of the CPU, there's no easy way to find out whether you have a real, proper, newer mask. If you have a good thermometer and/or can measure your 5 volt current draw, you can compare the old CPU with the replacement, but other than writing some tricky code to look for specific errata in certain models, there's no straightforward way in software to see what you've got, so try to go with sellers that have high seller ratings.
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