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Michael_b

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Everything posted by Michael_b

  1. Michael_b

    SE/30 Power Supply: Recap or ATX?

    Adding a data point here: I recapped the Apple Singapore version of the SE/30 power supply earlier this spring (same PSU as what @thxkbye, @iamroot have posted in this thread). It seems that capacitor leakage is a huge issue on these PSUs: mean looked similar to the picture above, and there was a large amount of cap goo on the metal enclosure as well. In the areas where there are black spots, the solder mask is easy to scrape off. Fortunately, the copper appears to be 100% intact underneath. I scraped off the marginal solder mask, replaced it, and installed new caps. Now the power supply works fine with normal voltages. So, if you have one of these supplies, even if it looks *really* bad, I think it is worth recapping. It's a single layer board, so desoldering is a fairly easy task. The only difficult cap is the big one, which requires drilling a new hole.
  2. Michael_b

    Arduino SCSI device - Work in Progress

    This is a great project and I am definitely in for (at least) one!
  3. Michael_b

    RaSCSI Development Thread

    Amazing work!
  4. Michael_b

    RaSCSI Development Thread

    Great stuff - very interested in the results of your testing!
  5. Michael_b

    Mac Plus or Mac SE?

    Are the capacitors original?
  6. FWIW my SE board which came with the SE/30-style chassis has no cutout.
  7. Michael_b

    IMG_6705.jpg

  8. Michael_b

    Issues with Mac SE/30 display (and more?)

    I would expect a large red film cap to look like the attached - in fact I grabbed that image from the cap kit you linked. Are you sure you didn't actually install the cap intended for C15 into the C12 spot? The original C12 cap is a film capacitor, so I think it would be an easy mistake to make. Also your C12 looks oversized relative to what I have on my analog boards. There's really not a good reason to replace C12; it's not electrolytic so it's not plagued by leakage as the other caps are. C15 on the other hand is electrolytic on the stock board - however, finding the correct value non-polar electrolytic is difficult/expensive, so the film capacitor is a common swap (though film capacitors aren't exactly cheap). If you have a polar cap in there, it's going to be wrong no matter what direction you've got it, AFAIK. If it is the flyback (don't ask me, I don't know), you might find this to be of interest.
  9. Michael_b

    Issues with Mac SE/30 display (and more?)

    Can’t quite tell from the picture but C15 on the AB looks polar, I believe that should be nonpolar.
  10. Michael_b

    RaSCSI Development Thread

    See here.
  11. Michael_b

    RaSCSI Development Thread

    I have it a go a while back but I accidentally reversed the SCSI connector pinout (went off a diagram for the male rather than female...) and haven’t had the chance to revise it. IIRC the PCB design linked to in this thread is slightly wrong and will require modifications (Cutting traces and patch wires) to work. Good luck with your efforts and please report back - the only other info I have regarding RaSCSI and old Macs is someone who claimed to have it working but only on 68030 Macs - said older Macs didn’t work.
  12. Michael_b

    SE/30 with an expansion card

    I think you might find this thread useful, if you haven’t already seen it. As you speculated, it seems that cutting the CRT is pretty difficult, so forming a mold might be a better route. It also seems that it would be worth trying to connect your SE/30 graphics card to any LCD panel you install in there - you’d have a grayscale SE/30 for a fraction of the cost.
  13. Just got this Power Mac 7200/120 for next to nothing. Only upgrade is a two port USB card. Nothing too exciting. It seems that the SCSI hard drive (Quantum Fireball SE) in this thing is dying. When I turn it on, it starts booting and gets into the Mac OS 8.6 screen very quickly. Unfortunately it hangs there, and the HDD starts making weird noises. Here's a YouTube video with audio - it sounds a bit sketchy at first, then seems like a normal (old) hard drive until about twenty seconds in. After that, it makes a loud buzz - then a tick-tick - then a buzz - then a tick-tick, etc... Is this a common failure mode for these drives, and if so, is it fixable? I'm planning on installing an SIL3112 either way, but I'd love to have the drive for an SE/30.
  14. Sad. Guess I'll take it apart, then move on. Need to find out what that buzzing is coming from...
  15. Michael_b

    Trick to desolder thru holes?

    I have an 858D clone hot air gun that I use in conjunction with the iron when I have to deal with a ground plane soaking heat up. If the iron isn’t enough, usually adding the hot air will provide enough heat to clear things out. In my experience, copper wick will just soak up even more heat, which is a problem if the ground plane is posing an issue on its own.
  16. Michael_b

    CRT portability

    See here. looks like you can borrow from 128/512, Plus, SE, SE/30, and some classics.
  17. I have a weird problem with a 12" 640x480 display. When I first turn it on, the picture is extremely squished vertically - otherwise fine. Over about 10-15 minutes, the display gradually stretches vertically until the picture looks normal. This happens so slowly that it really is imperceptible. I'm guessing this is a capacitor issue, though would be good to hear if there is another potential fault before I decide to invest any time/money into repairing this. Thoughts?
  18. I maxed out the vertical width with little effect. If it is the flyback, I likely won’t bother to repair it... though it does seem like the electron gun is shooting just fine, it’s just not being deflected up and down enough to reach the top and bottom of the tube. In that case, would the flyback still be the primary suspect?
  19. Well, I replaced every single electrolytic capacitor in the monitor. Annoyingly, the display is still letterboxed, though now it doesn’t get any better over time. What else could it possibly be? I don’t imagine I’ll put any more time into this monitor, but I’m curious as to what could cause this problem.
  20. Michael_b

    iBook G3 Snow White 2001

    Perhaps, but the MacBook keyboard doesn’t emit a pronounced smell of body odor, which is common on these machines due to the adhesive used on the keyboard...
  21. Michael_b

    Network laser printer for old / modern Macs?

    +1 on Netatalk, it’s what I plan to do - this reddit post has a pretty good how-to. Ultimately this means that most any laser printer will work fine, just doublecheck linux support as @cheesestraws said
  22. Just got a Beige G3 Desktop. Someone in the past has installed an OWC G4/550 upgrade, which was a nice surprise Are there any drivers necessary to use this CPU in OS 9/OS X? It seems that the answer is no, but I don't know if there's any functionality that is missing without drivers. I'd like to get this thing clocked as fast as possible while staying stable. I was messing around with the jumper settings as seen on this site, and I found Does not post at the 83.3MHz bus speed, so that's not an option. It does work to either: have 33.3PCI/66.7BUS/533CPU speeds have 35.0PCI/70.0BUS/560CPU speeds have 30.0PCI/75.0BUS/600CPU speeds What is the compatibility penalty to running the PCI bus at a speed other than 33.3MHz? From what I've read, it shouldn't matter that much - is this correct? Is there a performance penalty to running the PCI bus at 30MHz, rather than 33.3MHz This is particularly relevant as the fastest clock I've been able to achieve has necessitated a 30MHz PCI bus Most importantly, is there a way to obtain a higher bus speed multiplier than 8.0x (see attached picture)? The website suggests that this is unknown/impossible - is this correct? If this were possible, it would allow speeds of 566/600/633/667 while keeping the PCI bus at 33.3, which would be nice I'm looking at getting a Radeon PCI 7000 or 9200/9250, so if anyone has any specific recommendations in that regard they would be appreciated!
  23. Just retested using Newertech's Gauge Pro. The additional jumper settings may be correct: 1,1,1,1 gets 600MHz, or 9x the bus speed 1,0,0,1 gets 667MHz, or 10x the bus speed Weird that System Profiler reports a different number, though I've heard it can't be trusted. Either way, pretty happy that I've been able to squeeze another 133MHz out of this processor. Will need to benchmark further to see if it is a.) stable and b.) actually running at these speeds.
  24. Michael_b

    Help setting up Ethernet with an SE/30

    +1 - I have one of these cards, so I'm also curious. I haven't gotten a chance to test mine. Interestingly enough, the chip for U8 has identifying markings ground off and replaced with an Asante label on mine, while it is not concealed on yours. Looks like it is a PAL chip. I've never seen that particular ethernet daughterboard, however. I've seen the T7220 and the LXT902PC chips used, but the chip on yours appears to be 24(?) pins - very curious to know what IC that could be.
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