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davidg5678

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  1. While looking at a spare SE/30 motherboard, I noticed a similar-looking diode which was also labeled D3. In addition to this, it was located near both the SCSI connector and a fuse in the same way the diode on the Mac Classic was. I was not able to find a part number for the diode in the Classic's schematics, but the SE/30 schematics list D3 as a 1N4001 Diode. The circuits seem to be slightly different from each other, but I am hoping that they are similar enough to both use the same part. My plan is to try using a 1N4001 as a replacement for the Classic. I am not 100% certain it is the correct component, but with any luck, it should at least be close enough to work.
  2. Does anyone know what a suitable replacement for the D3 (diode?) on this logicboard would be? Thanks!
  3. Sure! Those could certainly come in handy. Hopefully, I'll be able to identify and fix everything that is broken on the left side of the board, but the only way to know whether or not I can fix this machine is by trying. -Either way, it will be a fun endeavor. When you made the 14 pin extension cable for your SE FDHD project, did you need to buy crimping connectors along with the Molex socket? I was able to find this part on Digikey, but I wasn't sure whether or not to order 28 of these contacts too.
  4. I have not done any additional work on the motherboard since my last post, but I have been doing lots of research about how to fix the computer and what I need to buy. Despite the battery leaking acid all over the board, it looks like all of the traces are still fairly intact. Unfortunately, the condition of the pads on the board for many of the chips is quite poor, so I will have to run a lot of very thin wires from the traces directly to component legs. After re-reading @LaPorta's SE FDHD Restoration thread, I decided to purchase a very small drill bit set (the smallest bit is .5mm) so that I can attempt to drill out some of the destroyed vias on the board. Most through-hole components had become so corroded that I was completely unable to get the solder for them to melt, no matter how much flux I used. In theory, I should be able to drill out the corroded pieces of legs and proceed with installing replacements. It looks like the diode D3 is completely destroyed (the metal contacts were completely eaten through). Does anyone know the part number for a replacement? I also still need to find replacement parts for the programmer/reset switches and the headphone jack. Here are some better quality photos of the motherboard: (It looks like the forum's image uploader is working again!) Thanks for your help!
  5. Luckily, the RTC looks to be in reusable condition, but I suppose I won't know if it still works until after I put the motherboard back together. I was able to remove most of the corrosion from the pins of the ICs by soaking them in vinegar for a few days. I'm concerned that there will not be enough remaining metal that I can still solder to, but I won't know until I have tried.
  6. davidg5678

    Green stuff out of an SE/30 CRT?

    I wonder if the green liquid you found leaked out of the clock battery -when I was disassembling my Mac Classic that had leaky Maxell battery inside, the battery was noticeably wet with a gritty, black fluid. The corrosion on your motherboard does not look nearly as widespread as mine, so maybe the reason the liquid inside my computer was black was that it had had more time to corrode the metal. The damage done to your logic board looks fairly contained to the area around the battery, so I think it is probably repairable.
  7. I recently purchased a battery leak damaged Macintosh Classic, and to no surprise, upon opening the machine, I discovered that the battery had leaked and corroded the inside of the computer. As a challenge, I am attempting to repair the broken motherboard and get the computer working again. Aside from a damaged motherboard and metal chassis, the computer was in fairly good shape and cleaned up nicely. I was able to sand down and repaint the chassis, so it is no longer an issue. The logic board of the macintosh was initially covered in lots of residue from the leaky Maxell battery, but I have since cleaned it off. Many components were so corroded, they fell right off of the PCB and I had to throw them out. (The forum's image uploading seems to be down at the moment, so here are some links to pictures.) (Before cleaning) https://imgur.com/DSoSj8c https://imgur.com/WViqnj2 (After cleaning) https://imgur.com/9lbCmOl I desoldered every component in the vicinity of the battery and discarded everything that was beyond recovery. I also soaked several of the worst looking chips in vinegar, which removed the corrosion from their legs. Without components in the way, it was easy enough to clean off the PCB. Now that the board is clean, I now need to figure out how to repair it. --Assuming it's possible of course. The issue I have is finding the right parts to buy, but as of now the following components are missing or damaged: Headphone Jack Programmer's and Reset Switches SCSI Port Battery Holder L1 (Inductor?) Y1 Crystal J2 Serial Port D3 (Diode?) If anyone has suggestions about fixing a logic board as damaged as this one, I'd be very interested to hear them!
  8. davidg5678

    davidg5678's Computer Finds

    Here are some photos of the restoration of the ADB Mouse: Mouse before cleaning and retrobrite: The adhesive meant to secure the smooth plastic strips on the bottom shell had turned a dark shade of brown, and the bottom of the mouse was significantly yellower than the top. (Also notice the color difference between the bottom housing and its label.) In order to restore this mouse, I had to disassemble the housing and clean both halves thoroughly with cleaning spray. (The mouse was small and simple enough that soapy water was not necessary.) After this, I pried up the friction-reducing strips from the bottom of the shell and scrubbed them with isopropyl alcohol until all of the brown adhesives were removed. (I then replaced the adhesive with some double-sided tape) I also used isopropyl alcohol on a paper towel to clean the dirt from the cable. Once this was done, I decided I would retrobrite the plastic. I have not had much success retrobriting before, but because of the small size of the mouse, I was able to completely submerge it in hydrogen peroxide from the drugstore. I kept it underneath some UV lamps for about 18 hours, and I am very pleased with the results. After cleaning/restoration:
  9. davidg5678

    davidg5678's Computer Finds

    I have now (more or less) completed the task of cleaning up the remaining peripherals. The keyboard was by far the most difficult to clean aspect of the project due to the irregular shape of the keys, and so it took the most time to restore. Otherwise, everything went fairly smoothly. Keyboard before cleaning: As you can see, quite a large amount of dirt built up between the keys of the keyboard, so it was necessary to completely disassemble and clean the entire unit. Once inside, I discovered yet more dirt which had fallen under the PCB. I separated each component for deep cleaning. In order to get the keycaps cleaned, I decided to use the same hot and soapy water method as before, so I carefully removed each and every keycap and placed them inside the bottom plastic shell. I let the keys soak for a while and then scrubbed each and every key individually to remove the grime. It took over an hour of scrubbing before I was able to get everything clean. The main plastic housing cleaned up without any trouble. After drying everything off, I reassembled the keyboard. It looks and feels MUCH better to type on; however, I discovered that the keyswitches for the left shift key and the number pad's nine key were broken. The white plastic plunger had cracked and caused the switches to not be as springy as the others. I was able to find replacement parts for sale, and I plan to replace the broken mechanisms. I also plan to retrobrite the entire keyboard in the future although submerging so many keycaps may prove difficult. After cleaning: Stay tuned for photos of restoring the mouse and monitor!
  10. Is it possible to do this if the disks are not ProDOS formatted?
  11. My Apple IIgs only came with a single 3.5" floppy drive, and I would like to use it to run some games and software which came on 5.25" floppy disks. I have ADTPro set up and working, but I am not able to use this setup for transferring games without a 5.25" floppy drive (at least according to the documentation). Is there a way to convert a 5.25" floppy disk image so that I can use it on the 3.5" disks? If not, is there another way (short of buying a FloppyEmu) that I can get software onto the computer? I do have an AsanteTalk, so I could try A2Server, although I'm not sure if that would be helpful in this situation. Thanks!
  12. davidg5678

    davidg5678's Computer Finds

    I have finished cleaning up the Apple IIgs which works perfectly (as far as I can tell). Before cleaning, the computer was covered in a thick (and difficult to remove) layer of dirt. There is an unusual bulge in the back of the plastic housing here, but I am not sure how it was made. I began the cleaning process by removing the top cover from the computer and taking out the power supply and memory expansion. Luckily, the clock battery had not leaked inside the computer, but I removed it anyway to be safe. It was manufactured in May of 1988. After this, I removed the motherboard from the computer and set it aside. The amount of dirt on the outside of the computer made it difficult to clean with just paper towels and cleaning spray, so I decided to completely disassemble the machine and use soapy water. I removed the motherboard from the bottom housing and then used flush-cut snips to clip off the plastic tabs holding in the metal shielding. I did this because there was a ton of dirt underneath the shields which I need to remove. Additionally, I did not want any water to get trapped underneath the metal and cause it to rust. Once all of the metal was removed from the case, I was left with three pieces of plastic. I rinsed each of these with hot water and dish soap inside a utility sink. I found a very useful small paintbrush to break up dirt trapped inside of the decorative lines and around the ports while I was cleaning them. This process left the computer looking very clean, and after drying the plastic, I put the machine back together. Beforehand, I had used a brush to remove loose dirt from the surprisingly clean motherboard. The metal shields snapped back onto the pegs that they were previously secured under even after I had cut them, so I did not need to do anything to repair the missing plastic. The shielding was still securely held in place and it even held up to being shaken. After cleaning: The computer still has some minor dirty areas which I'll need to clean up later, but it looks much better than it did before. I was able to follow a similar process to clean the external floppy drive with the obvious addition of cleaning and relubricating the drive mechanism. Next up are the mouse, keyboard, and monitor!
  13. davidg5678

    davidg5678's Computer Finds

    I came across this listing on letgo a few days ago a knew I had found a deal worth looking at. The seller was offering an Apple IIgs, a Macintosh SE, and a Macintosh Classic for all of $52. After a few hours on the road, I have returned with three computers to work on along with a pile of documentation, software, and accessories. I am particularly excited about the Apple IIgs, as I have always wanted to use an Apple II, but have never seen one for sale before anywhere near my area. The Classic has what looks to be some battery leakage residue on the rear case, so I'm not sure about whether or not it will be salvageable. --I'll have to open it up and see what happened... All of the computers are dirty and in need of a cleaning, but they appear to be in good enough shape otherwise. I was able to verify that luckily, the battery did has not yet leaked inside of the IIgs. Now to fix and sort all of the computers!!!
  14. davidg5678

    3D-Printed Objects

    Would it be possible to design 3D printed plastic CRT Adjustment Tools for use inside Macintosh CRTs? It is getting harder to find these toolkits online, and they just seem to be specially shaped pieces of plastic. Is there anything special about the tools, or would normal PLA plastic be safe to stick into an Analog Board?
  15. davidg5678

    Extended Keyboard II troubleshooting

    While doing research about ADB to fix my SE/30, I found a very useful ADB keyboard troubleshooting section in the book "Troubleshooting your Macintosh" by Douglass High. It is available on vintageapple.org. I would recommend trying all of the troubleshooting steps in the ADB chapter. (Be sure to verify the circuit on the SE/30 board itself.) Inside the ADB port, only a single wire is transferring data from both the keyboard and mouse, so the keyboard should work when the mouse does. (At least as far as I can tell from the cryptic "Inside Macintosh" books.) Are you able to use the mouse when it is daisy-chained through the keyboard? Do the caps-lock key and LED work? It is possible one of the ICs on the keyboard is not working correctly. Hopefully, the chips themselves are functional and the problem lies in how they are connected somewhere else in the circuit. Are you able to post some photos of the circuit boards inside the keyboard? Good luck!
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