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    IIci with potentially dead 50MHz oscillator.

    Alright, did that, and now the 68030 is getting a clock signal (it should be a sin wave, right?).  But I'm still not getting any signs of life out of it -- no chimes of any kind, no activity on the address lines.  If I hit the reset button, all the address lines, as well as the AS signal, go...
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    IIci with potentially dead 50MHz oscillator.

    Found it; I'm actually reading an open circuit across R89 as well as R87.  Continuity between MDU-106 and R89, and between R89 and CPU-6 are both fine, and I can see the 25MHz clock on the MDU side of R89.  That would probably explain it.  What size SMD resistor would I need to replace it with? ...
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    IIci with potentially dead 50MHz oscillator.

    I got the replacement oscillator and now I have a 50MHz wave, but like the above poster, the IIci still doesn't boot.  I tried probing pin 6 of the 68030, which is supposed to be the clock input, but there's nothing there.  Does anyone know where that's supposed to connect?  I looked at the...
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    IIci with potentially dead 50MHz oscillator.

    I'm trying to resurrect a IIci which had a Maxell bomb go off, which I caught before the damage was too bad, and only really ended up eating a couple of traces which I patched; I then recapped the entire board.  Using the ATX power supply mod, I'm able to get power to the board, but I have no...
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    IIci dead PSU?

    Alright, I ordered all the caps I will need (cost me less than $10 including the huge ones).  I didn't really listen for the click, but then again, I wasn't really listening for it.  If the relay was clicking, then wouldn't that imply that I should be seeing voltage on the 5V rail, even for just...
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    IIci dead PSU?

    So I've got my hands on a dead IIci, that came seriously dusty, and with a Maxell bomb having just gone off, but recently enough to be fixable (no rotten traces).  While I wait for the replacement caps to come in, I thought I'd turn my attention to the PSU.  First thing I did was probe pin 10 to...
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    Quadra 950 - Blank Bezel to CD Bezel Kluge

    What is the piece of plastic hanging off the bottom that looks like it prevents the drive from retracting all the way?
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    Will a IIx accept this RAM?

    I put in the 4 sticks I got off eBay into bank A, which normally holds the 4MB this machine reliably boots with, and it sad macs; they're 3-chip SIMMs, and I've read here that the IIx doesn't much like those. The slots are all fine; there's one chip out of the original 8 that is loose in...
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    Will a IIx accept this RAM?

    Well, looks like maxing out the IIx is outside my budget at this point due to how expensive those PAL SIMMs are.  I'd like to get it to at least 16MB or so, so these should work, right...
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    Will a IIx accept this RAM?

    I bought some 1MB SIMMs a little while back but the IIx just sad macs, so I figured I might as well check here.  4x16MB SIMMs.  I know I'll need either Mode32 or a IIsi ROM to use them, but other than that, are these compatible?  Can I just stick the existing 4x1MB in Bank B...
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    Macintosh Quadra 700 Battery Leakage

    There was a post here that had high resolution images of the entire board, but the embedded image links were all broken.  Here's a link to the actual images...
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    Macintosh Quadra 700 Battery Leakage

    Speaker clicking but not chiming could be a ROM issue.  If the CPU can read the death chime from the ROM, it should play it.  I don't have a schematic for the Q700, but there's a good chance that chip is important (since most chips are).  At the very least, I'd start with replacing the...
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    SE/30 doesn't play the chime on cold boot, but does on reset?

    I just finished recapping an SE/30 (logic only, I'll do the analog+PSU after I get their caps), and now I have a new problem.  When I cold power on the machine, I get a speaker pop, and the screen comes on with a blinking floppy as expected, but I get no chime.  If I then reset the machine, I...
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    Advice on repairing Mac IIx

    Just a quick update, there was one more bad trace between the NuBus slots and the batteries; after patching it up (that's the 13th patch on this board) I get video out and the machine is working like a charm!  It has a physically enormous hard drive (5.25in half-height, the size of a CD-ROM...
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    Need help hunting the other end of a trace on a SE/30

    That's the address bus.  That notation means that the address bus also occurs on pages 1-6, and is 32 bits wide.  The line you're looking for is A0, the least significant bit.  From a quick look through the pages of the schematic, it connects to the 68030, as well as to UK6 pin 10 and UD8 pin 4.
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    Macintosh 128k Help

    Could this be caused by a bad mux or demux (assuming the 128K has anything like that) causing the same data to be stored multiple times to the framebuffer?
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    Just ordered an SE/30, what should I expect/prepare for?

    I'm ordering the new caps for the SE/30 (and a Classic II and Plus that also need attention), but can't seem to find 50V 1uf tantalum caps.  Can I just use SMT ceramics for those?
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    Just ordered an SE/30, what should I expect/prepare for?

    I intend to :) .  But the SE/30 (which arrived today) is currently number 3 in line for my attention, which is currently on a Mac IIx and why I can't get any video out of it.
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    Advice on repairing Mac IIx

    I'm still not able to get any video.  I'm pretty sure the machine is booting, since it chimes and then starts reading from disk.  I tried two different video cards (a Macintosh II High Resolution and a Macintosh II video card), at least one of which is known working.  Is there any way to narrow...
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    Can I use one of these SCSI adapters on the internal SCSI bus?

    So essentially I can use any disk I want regardless of size, but I just have to partition it into disks of up to 2GB? Does this still hold true under A/UX?  I'm thinking of installing that on the IIx.
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