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davidg5678

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  1. I just tried switching my SE/30 Logic Board with one from my Macintosh SE, and I was able to boot up the computer without any problems at all. The display looked fine and stood up to a smack on the side of the case, and the PSU had solid and normal voltages. This probably means that the problem lies in the video circuitry of the SE/30.
  2. My recapped SE/30 (analog board, logic board, and PSU) has begun to exhibit a strange problem. When I flip the power switch on, one of four things happens: Fan Spins, No video output Fan Spins, Extremely Garbled Video output (see video #1) Fan Spins, Thin vertical line briefly flashes on the screen, no video output (I was unable to recreate this) Fan Spins, Thin horizontal line briefly flashes on the screen, no video output (see video #2) After checking the components on the motherboard, analog board, and PSU, everything seems to be intact, and I did not see or smell any burning parts. I am unsure what to test next or what might be wrong with the machine as this does not resemble any single issue I have read about. I am happy to provide more pictures of the circuits. Please let me know if you have any ideas about how to fix this. Thank you! SE30_HorizontalLine.MOV SE30_GarbledVideo.MOV
  3. davidg5678

    G3 B&W motherboard upgrade to G4

    I would recommend searching online for a Hardware Test ISO to burn as there is no advantage to getting an original CD that may or may not work.
  4. davidg5678

    Recommend a support Mac for my Color Classic Mystic

    A Powermac G5 is capable of running both 10.4 Tiger and 10.5 Leopard. A new enough and well upgraded G5 can survive somewhat decently on the modern-ish internet using the 10 FourFox browser. These operating systems are both capable of writing to HFS partitions without any hacks. (Meaning that Zip or Floppy disks can be directly used.) 10.4 Tiger is also able to run the classic environment as a compatibility layer for OS9 and below. This means you could probably decompress stuffit files with appropriate software. In terms of burning CDs, I believe it is possible to do under the most recent operating systems as an iso file does not get decompressed during the burn process. What would probably be preferable would be to look for a Beige PowerMac G3 machine as they are some of the most powerful computers with compatibility for older Macs (features including USB, ADB, Ethernet, LocalTalk, Floppy/Zip Support, and SCSI. They also can run OS8 through 10.2.8. A G4 Tower or Laptop would also be better than a G5 as many can boot directly into OS9 (which is better than classic) while doing everything else the G5 can without being as massive. Before buying anything, I would highly recommend checking the exact model for compatibility with the OS you want. (Not all G4s can run OS9.)
  5. Thanks for the suggestions! I have successfully patched the trace. I initially tried to cut away the destroyed chunk of trace and run a patching strand of wire but damaged the ends of the trace too much to allow for it to happen. I then decided to run a wire from point to point instead. Because I would have had extraordinary difficulty following the trace by hand, I took several pictures of the board and drew a line following the trace's path on my computer. (See attached images.) After this, it was easy enough to just run the wire. I now need to figure out a way to keep it from accidentally getting ripped from the board... My current soldering iron is a standard 40 watt Weller that has no temperature adjustment features. It has worked well in the past, but it might be time to get a nicer soldering station. I was able to clean up the pins on the rest of the components and make them shiny again. --Now for attempting to repair the pads and replacing the destroyed components. Does anyone know what part would be a suitable substitute for D5 and D6? It looks like they are a sort of surface mount transistor.
  6. Can you explain how to do this? I set my multimeter to ohms and measured between the two sides of the battery holder, but couldn't get any reading. Trying to do this has created a much larger problem. Some of these reflowed without a problem, but it looks like the pads on a few were terribly corroded as they fell apart when they were touched by my iron. I am now left with some destroyed pads and a very damaged trace to repair. Does anyone know the way to repair something like this? Thank you!
  7. Thank you for your responses -I apologize for the delay as I was on vacation. After writing my original post I decided to check the voltage of the batteries inside the mac. I had figured both batteries would be working as I had installed them brand new the month before. To my surprise, one of the batteries was reading .6 volts and the other 3.6 volts. I replaced the .6 volt battery with a brand new one and the computer's power circuit started to behave slightly better. I was able to use soft power unreliably for about an hour until it stopped working again. The voltage on the Power Supply Control pin was even closer to the 5 volts it should be instead of the .6 volts from before. I went on vacation after this and upon returning found that my brand new battery had been drained to about .6 volts. The other battery was still normal. I checked the voltages that AwkwardPotato suggested but found them all to be at least a volt too low. --Maybe this is due to one the dead batteries? I also noticed that the legs of Q3 and Q4 looked slightly less shiny than their surroundings. I will try to reflow these with fresh flux and solder. Is there anything that would cause the battery to die so quickly while the computer was unplugged? I have attached some pictures of the motherboard. Thanks again!!
  8. As referenced in a previous thread, I am working on restoring a Macintosh II. This machine’s power-on circuit seems to be broken. The entire logic board has been recapped and cleaned to the best of my ability -I also repaired several damaged traces. Two 1/2 AA batteries have been installed in sockets. When I press the power button on my keyboard or at the back of the machine, nothing happens at all. I am able to run an alligator clip from one of the batteries to the rightmost PSU pin in order to jump-start the computer, but this is definitely less than optimal. I checked the PSU voltages under load and verified they are all within .2ish volts of normal. I also noticed that when the machine is powered off and I read voltage between the rightmost PSU pin and ground, I can make the value spike to .6 volts from 0 volts upon pressing the keyboard power button. I am not sure if this is normal behavior. (maybe someone can verify?) After being recapped with repaired traces, is there any obvious reason I have these issues? Please let me know if you have any ideas. Thank you! I am happy to provide more information and/or photos.
  9. davidg5678

    Creating HFS Images in macOS?

    I have been experimenting with something similar after reading about it in another thread. With the Basilisk II emulator, it is possible to mount Zip Disks containing a bootable MacOS installation directly into the emulator on a modern mac. Basilisk II is able to view the modern mac filesystem from within emulation as a drive labeled Unix. I am able to download files from the internet, decompress them with The Unarchiver under High Sierra, and then view and copy the files directly onto the Zip Disk from the emulator. The Zip Disk can then (theroretically) be booted on original hardware. This method should also allow for booting off an image on the modern mac and just mounting floppy disks in the emulation.
  10. davidg5678

    Ext floppy drive stuck?

    Isopropyl Alcohol on a Q-Tip does a very good job removing the old grease. As clean as your drive may be, there is a high chance that there is dust buildup on many different places in the drive. Carefully following the above video is probably all you need to do in order to get everything up and running again. The video details how to disassemble the drive mechanism which will allow you to move the jammed mechanism back into position.
  11. davidg5678

    LCD screen in a Color Classic

    The previously linked 9.7 LCD is the exact same panel that is used inside of the iPad 3 and iPad 4 and can be purchased on eBay for as cheap as $20. This will need a driver board which costs around $40. The results of the iPad sized LCD in a compact mac can look pretty decent. http://osxdaily.com/2010/06/20/mac-plus-ipad-case/ --This is not a color classic, but the screen size is still the same. The addition of a Raspberry Pi running an emulator and an ADB to USB adapter could make a pretty interesting machine. The driver boards make use of HDMI which probably could accept an actual machine's input with the correct active converters.
  12. davidg5678

    Recapped Macintosh II will not boot

    Unfortunately, things were not as easy to repair as I thought. After a few days, the computer does not want to turn on with soft power at all. After I jump-start it, I am able to get the machine to boot from a floppy disk with Norton Disk Repair Software on it (the only bootable 800k floppy I have right now.) I was entirely unable to get the machine to boot from my SCSI2SD with System 7.5.5. It works perfectly in my iisi and SE/30. The stock Hard Drive does not seem to work in this machine, and neither does a Zip Drive or the iisi drive. I suspect something SCSI related may be broken. I sprayed contact cleaner over all of the sockets and reseated the chips, but this did not help. I am unable to see any damaged traces on the board apart from the ones which I have repaired. If you have any ideas what might be wrong, please let me know. Thank you!
  13. davidg5678

    Recapped Macintosh II will not boot

    After taking a closer look at ROM4, I noticed that only half the pins were inserted in the socket. I had removed all of the socketed chips when I cleaned the logic board with isopropyl alcohol, and I must have not put the chip back in correctly. After removing it and placing it in the socket the correct way, the computer was able to turn on. The hard drive seems to be long gone, but I was able to boot from a floppy disk successfully. Now to configure the computer... My method for repairing traces involved scraping the solder mask off from either side of the corrosion, using flux to place a bead of solder on the exposed copper of the trace, and running a very small piece of wire over the gap. (I used tweezers to scrape the solder mask and hold the wire in place.) I may go back and place a blob of hot glue over everything to keep it in place. Thanks to everyone for their help!!! I will keep this thread updated if I encounter any more issues. I am unsure whether or not repairing the traces and recapping were even necessary at this point, but they certainly did not hurt the computer.
  14. davidg5678

    Recapped Macintosh II will not boot

    I repaired the broken trace above C7, the trace near the power button, and the trace near D4. I also replaced the 10uf 16v capacitor with a new tantalum one. It looks like there were already surface mount pads in place underneath the axial capacitor, so I connected to these. While working on the traces, I scratched off a little solder mask on each side of the corrosion, placed solder on the exposed copper, and put a thin wire over the gap. The system immediately powered on when I pressed the button on the keyboard -much better than before. Besides turning on the power supply when the button on the keyboard is pressed, the computer seems unchanged. There is still no boot chime, and the screen does not display any picture or do anything besides turn on. The hard drive stops accessing after about ten seconds into startup. This is about the same as when it was jump-started. Are there much more than three damaged traces to fix? Thanks again!
  15. davidg5678

    Recapped Macintosh II will not boot

    Thanks for the help! I will take a better look at the motherboard and try to fix some of the traces. With any luck, my Macintosh II will start working.
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