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AlexTheCat123

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About AlexTheCat123

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    Columbia, South Carolina

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  1. AlexTheCat123

    Macintosh Quadra 700 Battery Leakage

    Can you tell me the code on capacitor C61? I can read all of the numbers on all of the components except for that one.
  2. AlexTheCat123

    Macintosh Quadra 700 Battery Leakage

    Thank you! That is perfect!
  3. AlexTheCat123

    Macintosh Quadra 700 Battery Leakage

    Thank you for the picture! Unfortunately, I can't make out the values of those parts, so those additional photos would be great!
  4. AlexTheCat123

    Macintosh Quadra 700 Battery Leakage

    Can someone upload some pictures of the area of the board near the reset and interrupt switches? I am trying to order replacement parts and I want to make sure that the component values are what I think they are. There don't seem to be any pictures of that area in the link that tattar8 provided above.
  5. AlexTheCat123

    Macintosh Quadra 700 Battery Leakage

    Thank you for this advice. I will try to resolder the parts that fell off and I hope that my RAM chips aren't bad.
  6. AlexTheCat123

    Macintosh Quadra 700 Battery Leakage

    Thanks! I will look into that.
  7. AlexTheCat123

    Macintosh Quadra 700 Battery Leakage

    Do you know the values of the components that I listed above? They disintegrated when I was cleaning the board so I don't know what to replace them with.
  8. I recently bought a Macintosh Quadra 700 off of eBay (https://www.ebay.com/itm/Vintage-Apple-Macintosh-Quadra-700-M5920-Desktop-Computer-w-Harddrive-Mac-iMac/273781054522?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m2749.l2649) and it has some corrosion on the logic board from a leaky battery. When I was cleaning the corrosion off, several components fell off of the board. The parts that came off were R71, C61, R76, R77, Y6, and C65. D5, D6, and U91 are still on the board, but their pins don't look too great. U92 has nearly all of its pins broken off and it is hanging on by two or three pins. I tested the continuity of all of the traces that I could follow in the damaged area and everything seemed to be connected. When I try to turn the computer on, the power LED lights up and the speaker clicks once (but does not chime). Do you think that the symptoms are caused by the missing parts or are the power-on issues more likely the fault of bad traces that I didn't catch? If any of the missing parts are necessary for operation, please tell me the correct component value so that I can replace them. I hope that U92 is not needed for the machine to power on because it seems to be a custom chip that is probably impossible to find. Attached are some pictures of the damaged area so that you can see what I am referring to. I hope I can save this one because I have always wanted a working Quadra 700!
  9. AlexTheCat123

    Macintosh IICX No Video After Recap

    Sorry for the late reply, but I checked the resistor network the way that you described and it seems to be fine. I don't know what the problem is at this point. Do you think that I should just give up on it?
  10. AlexTheCat123

    Macintosh IICX No Video After Recap

    How would I go about testing that part? What does it do exactly?
  11. AlexTheCat123

    Macintosh Color Classic No Sound After Recap

    I guess the chip itself is just about the only thing left that could be fried. I will try to order a replacement and get it installed to see if the IC is the problem.
  12. AlexTheCat123

    Macintosh IICX No Video After Recap

    Yes. I have already cleaned the floppy drive and it works fine. The computer still exhibits the symptom even when the drive is unplugged, so the drive itself is not the problem. In addition, the dialog box asking to initialize the disk shows an arrow pointing to an external drive, not the internal drive. It thinks that I am inserting a disk into a drive connected to the external floppy port, even though I don't even have one connected.
  13. AlexTheCat123

    Macintosh Color Classic No Sound After Recap

    It turns out that I was completely wrong about the bad part. I tested it again and it checks out just fine. I guess that I didn't make good contact with it the first time I tested it since it is so small. Now that I am certain that all three capacitors are good, I am not sure what is wrong. Any ideas? Some pictures of the amplifier circuit can b found in the above post.
  14. AlexTheCat123

    Macintosh IICX No Video After Recap

    It turns out that the problem was indeed with the RAM. All of the SIMMs were good, but one of the sockets that still had the tabs on it needed pressure applied to its SIMM in order to make a good connection. I simply wedged a small piece of plastic between the SIMMs to apply pressure and now it mostly works great. However, when it is at the blinking floppy disk screen, it constantly flashes the floppy icon with the x over it, even when there is no floppy in the drive. I unplugged the hard drive and floppy drive as well to confirm that they were not causing this. Once I had an OS installed on the computer, I found out that the strange problem continued, in the form of an alert repeatedly popping up telling me that a disk is unreadable and needs to be initialized. The icon that it showed pointed to a disk in an external drive, even though there was not one connected. Each time I hit the "Eject" button on the menu the menu would disappear but it would come back a few seconds later and ask the same thing again. The only way to make it stop was to insert a floppy disk into the internal floppy drive. After I inserted the disk, the message went away and it never reappeared, even if I removed the floppy from the drive. I think that something might be messed up on the logic board near the external floppy port. What do you think is going wrong here?
  15. AlexTheCat123

    Macintosh IICX No Video After Recap

    Perfect! I will try to test the SIMMs in my SE tomorrow afternoon and see if any are bad.
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