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Recent content by douglasgb

  1. douglasgb

    PowerBook 500 battery replacement

    I'm not sure of the best way to open these - I tried to pry mine open at one of the gaps and it shattered as I did so. Maybe the leaking battery gasses also weakened the plastic? There are other threads here showing other people's attempts. When I get up the nerve to do my second battery I will...
  2. douglasgb

    Kingston KTA-PB500/32 RAM

    Update: I've successfully upgraded an 8MB Kingston card to 16MB by adding chips and changing the jumpers. Here's the front of an original 16MB card; to make the 8MB match it just needed R15 and R17 jumpers, U13, U14, and U15 caps (which I transplanted from the 72 pin SIMM), and the four RAM chips.
  3. douglasgb

    PowerBook 500 battery replacement

    I have yet to calibrate the battery with a proper charge/discharge cycle, and may have trouble with the EMM that Lind/IBU/EMMPathy can't seem to fix. But the battery does run the computer and the computer does charge the battery! Notes: this project would have been much easier if my battery had...
  4. douglasgb

    PowerBook 500 battery replacement

    There is a short black wire from the EMM board terminal to the first of the battery contacts, and then finally the red wire was attached. I did that so the EMM board was unpowered until the very end. Next time I will achieve the same thing by connecting the black wire from the battery to the EMM...
  5. douglasgb

    PowerBook 500 battery replacement

    Here are the pieces laid out for assembly and the initial connections. Note that the lowest of the three small wires is attached to the bottom of the bottommost battery contact. That's because I wanted to leave the top empty for the final connection of the main positive lead from the battery.
  6. douglasgb

    PowerBook 500 battery replacement

    More bad luck: the corrosion had followed the copper all the way to the three small contacts on the EMM board itself. I desoldered that part and tried to clean it up, but two of the pads had been compromised. I was able to trace those two connections back to the nearest via, cleaned them out...
  7. douglasgb

    PowerBook 500 battery replacement

    Luckily the temperature sensors were in good shape, so I trimmed off the bad parts and left the good parts. This material is very easy to tear so be I was very careful on that interior corner.
  8. douglasgb

    PowerBook 500 battery replacement

    The battery I took apart had sadly been leaking, and after opening it I found the internal conductors were in bad shape.
  9. douglasgb

    PowerBook 500 battery replacement

    I got a pretty nice PowerBook 540c but of course the batteries were dead. After a lot of research and reading, I decided to try to make them work again. I did not relish trying to solder or epoxy batteries together. Given the advances in AA battery power, I decided I would try a ready-made pack...
  10. douglasgb

    Kingston KTA-PB500/32 RAM

    I found some inexpensive 8MB 72pin SIMMs that used the same chips (KM48C2100A) as the PB500 module. I was able to desolder the chips from the SIMM and add them to the 24MB card. I left the jumpers as-is since they already matched the pictures of the 32MB card. I crossed my fingers and installed...
  11. douglasgb

    Kingston KTA-PB500/32 RAM

    I recently bought a 24MB RAM card for my PB540c made by 'Advantage Memory' that has a few capacitors as well as zero-ohm resistors (jumpers) that I assume let the computer detect the size of the card. There was also a 32MB card for sale and I compared its pictures and noticed it had all of its...
  12. douglasgb

    Duo 210 keyboard misses keystrokes randomly

    I just posted my solution in the 'Improving a PowerBook Duo keyboard' thread:
  13. douglasgb

    Improving a PowerBook Duo keyboard

    Mine is much better. I did not use 'circuit repairer glue' which I assume is like CaiKot 44. I did clean them with a Q-tip and isopropyl alcohol. The real problem I found was that the two sheets of clear plastic that have the conductive areas were simply not laying flat, and making the keys far...
  14. douglasgb

    PowerBook external SCSI CD not working.

    If you have the cables, try Powerbook - CD - ext HD.
  15. douglasgb

    Changing Drive Icon?

    The non-PE version of FWB has a menu command for changing the default drive icon.
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