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  1. Important Information

    1. The 68kMLA Forum Rules   (7265 visits to this link)

      To quote vintage Apple manuals: "Read Me First!"

  2. Community Connections

    1. General 68kMLA News & Stuff

      What's going down in the barracks.

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    2. Conquests

      Discuss your latest vintage Mac finds!

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    3. Trading Post

      Feel free to trade all of your Mac goodies here with all honest intentions. The website provider assumes NO liability, so buyer beware! Please see this topic for more information.

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  3. Projects & Hosted Forums

    1. RetroChallenge

      What can you do given only one month and strictly "retro" hardware? Find out with RetroChallenge!
      http://retrochallenge.org/

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    2. 68kMLA Wiki

      The creation and maintenance of the 68kMLA's information repository.
      http://68kmla.org/wiki/

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  4. 68k Model Forums

    1. Compact Mac

      Macintosh, 512k, SE, etc.

      41698
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    2. Mac II, Quadra & Centris

      Just think, having a Quadra 950 in 1992 would be like having a Mac Pro today… except with more slots, more expandability, and on-board SCSI!

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    3. 68k LC & Performa

      Ah, the consumer computers!

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    4. 68k PowerBook

      From the Portable to the 190cs.

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  5. PowerPC Model Forums

    1. NuBus Power Mac, LC & Performa

      The NuBus architecture gets a new brain!

      2526
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    2. PCI Power Mac & Performa

      The PPC comes of age and adopts the industry standard expansion slot.

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    3. G3/G4/G5 Power Mac, iMac & eMac

      From the Beige G3 to the quad-core G5, via various iMacs!

      13017
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    4. PPC PowerBook & iBook

      All that power in a laptop? Never…

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  6. Everything Else…

    1. Apple I, ][, /// & Lisa

      Not really 68k Macs, but certainly Vintage!

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    2. Newton

      The best PDA ever finally gets its own forum!

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    3. Software

      Includes system stuff, productivity, emulation, design, and games for pre-OS X Macs!

      16432
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    4. Hacks & Development

      Yes, it's back! Hardware hacks/modifications and software development for Mac OS.

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    5. Peripherals

      Anything you can hook up to your Mac or stuff into it as an interface!

      13156
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  • Posts

    • The reason newer ATX power supplies have less capacity on the 5V line is that CPU power has long since moved to using voltage regulation from a 12V source. Back in the 68k days, CPUs were still being run directly off the 5V rail.
    • Okay, I've done more research on PSUs.    The original Quadra PSU outputs the following voltages: +5V Trickle 'Constinuous' @ 1.25A +5V 'Normal' @ 33A -12V @ 1A +12V (a) @ 5A +12V (b) @ 5A   Modern PSUs can output most of the voltages above with a higher amperage, except for the 5V rail. This is most likely due to the fact that the standard molex connector has been phased out. The more molex connectors a PSU has, the more powerful the 5V rail tends to be. Your average brand new ATX PSU can provide up to 20A on the 5V rail, same thing with the industrial ones. To put things into perspective, even the AX1600i, Corsair's flagship 1600W PSU can't go past 30A. Geekdot's PSU must have been a couple years old already as it too can do 30A.    I've checked with Seasonic and most of the other well known brands, and I couldn't find anything relatively new that does more than 28A.  I think I'll go with the Corsair VX550, a 40 euro PSU on the second hand market that can do 5V @28A. It also has 6 molex connectors. I'll only need four.    For the adapter board, I'd like it to handle a couple of things: 1/ Standard Molex to P4/64 Bit Power 4 Pin Square Molex conversion (DC side) 2/ Soft power (DC side)
      3/ Monitor out power (AC 'hot' side)   I'll start working on it right away.
    • I found out that some of the 74HC132 and 74HC74 were damaged (Power Circuit) by the cap goo. I've desoldered them and ordered new ones. Maybe that's an issue too.   Some pins of these chips were broken
    • Silly question, but what kind of Zip drive have you got ? the standard SCSI one or the Plus ?   IIRC the version on the driver is mandatory to get a working disk.    
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