Powerbook Duo 280c + Accessories Maintenance

jmacz

Well-known member
The battery cover won't stay attached to the battery as the clips were broken off. Tried a few things to fix it but none of them worked. Ended up spending time modeling a brand new cover.

Screenshot 2025-03-04 at 10.42.22 PM.png

First test print was close but I need to fix a few things. Will try a second test print tomorrow.
 

3lectr1cPPC

Well-known member
I have one from that same brand, yes. I've only rebuilt one battery with it so far (my PowerBook 1400 battery), so far so good. Works well.
 

demik

Well-known member
Is the PRAM battery the same Panasonic rechargeable thing as in the 1xx series ?
 

finkmac

NORTHERN TELECOM
The battery cover won't stay attached to the battery as the clips were broken off. Tried a few things to fix it but none of them worked. Ended up spending time modeling a brand new cover.
First test print was close but I need to fix a few things. Will try a second test print tomorrow.
very nice. very very nice.

now if only someone would model the side bumpers that love to harden and crumble to bits.... that would be so awesome. that would be so cool.1741360778697.png
 

jmacz

Well-known member
very nice. very very nice.

now if only someone would model the side bumpers that love to harden and crumble to bits.... that would be so awesome. that would be so cool.

I will see if I can spend time modeling it.
 

jmacz

Well-known member
Is the PRAM battery the same Panasonic rechargeable thing as in the 1xx series ?

Yes, same Panasonic VL-2330 rechargeable cell, but different count and configuration.

Duo and 190/5300: 2 of them stacked with three wired plug providing 6V, 3V, ground (the 3V wire goes between the two serially connected cells and only provides power from one of the two cells).

500s: 2 of them side by side with three wired plug providing 6V, 3V, ground (the 3V wire is again between the two serially connected cells and only provides power from one of the two cells).

100s: only 1 cell which is soldered directly onto a PCB.
 

jmacz

Well-known member
@finkmac modeled it... but need to try some test prints later to ensure the dimensions work. That said, going to be a pain to print due to the little diamond shaped standoffs inside it and getting the support structures in place.

Screenshot 2025-03-07 at 10.51.32 AM.png
 

jmacz

Well-known member
@finkmac, FYI I printed the side bumper model and it fits great. I printed it in PLA and of course since it's not that rubbery material, it's less forgiving when installing/uninstalling. I didn't do any sanding or anything in the picture below. Attached the STL model for the bumper to this post. The battery cover still needs some more work.

IMG_9552.JPG
 

Attachments

  • sidebumper.zip
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demik

Well-known member
Yes, same Panasonic VL-2330 rechargeable cell, but different count and configuration.

Duo and 190/5300: 2 of them stacked with three wired plug providing 6V, 3V, ground (the 3V wire goes between the two serially connected cells and only provides power from one of the two cells).

500s: 2 of them side by side with three wired plug providing 6V, 3V, ground (the 3V wire is again between the two serially connected cells and only provides power from one of the two cells).

100s: only 1 cell which is soldered directly onto a PCB.
Good to know thank you. I'm gonna order more for my 500 build
 

jmacz

Well-known member
Made a battery contact alignment tool based on the service manual and just inferring what it might look like. Not sure if it actually is to spec with the original tool from Apple but at least on my system, it did allow me to adjust the contacts where it's aligned properly now. Model available via the printables link in my signature.

Screenshot 2025-03-09 at 9.06.02 AM.png
 

jmacz

Well-known member
Final revision of the battery slot cover. It clips on to the battery well but still has good sliding movement which is great. Once the battery is in, the cover holds the battery securely to the main PowerBook Duo body. It's a bit on the stiff side so it takes a little effort to open it again. This is where I have been tweaking it to find a balance between good grip so it doesn't come open easily but also not being too difficult to remove.

IMG_9555.JPG

I still have to paint it although I don't have an exact color match with the power book so I think it will still end up darker, but not as dark as this black filament I used to print it.

I've got a couple more PowerBook Duo keyboards coming and I'm hoping at least one of them is in better shape than the one I received with this unit.

And then moving on to a Duo Dock I received which is completely dead. Well, there's some power going to it but it just keeps making a clicking noise and that's it. Plastics are in good shape though so hopefully this can be fixed. The power supply will need to be recapped but the logic board doesn't have any electrolytic capacitors so hopefully it's in good shape. This unit came with the extra VRAM on board as well as the FPU (which I won't be able to use since my Duo has a 68040).
 

3lectr1cPPC

Well-known member
Made a battery contact alignment tool based on the service manual and just inferring what it might look like. Not sure if it actually is to spec with the original tool from Apple but at least on my system, it did allow me to adjust the contacts where it's aligned properly now. Model available via the printables link in my signature.

View attachment 84273
Now I wish I had taken a photo of the one that showed up on eBay a few months ago...
 

Fizzbinn

Well-known member
Now I wish I had taken a photo of the one that showed up on eBay a few months ago...
I bought that one! I haven't tried to rebuild a Duo battery yet but thought it might be useful if it I did. Its also a nice paper weight ;-)

Here's a quick flat bed scan with a ruler in case that's helpful:

2025-03-09_171003.jpg
 

jmacz

Well-known member
@Fizzbinn nice!! What's it made out of, metal? Can you do me a favor and also snap a picture with the ruler showing the height? I need an accurate measurement of the height of the cut outs where the contacts are. Thanks!!!
 

jmacz

Well-known member
Yes, think it’s a solid block of aluminum. First AL unibody Mac product!?

LOL

Ok, I was very close. My widths were all spot on. The height was off by 0.5mm near the top (the large indent). And I had diamonds at the end of each contact groove (because that's what's shown in the service manual) whereas the real tool has a circular end.

I've corrected both issues in an updated model on printables (link in my signature). Thanks @Fizzbinn!!

Screenshot 2025-03-09 at 7.13.10 PM.png
 

jmacz

Well-known member
From reading a few threads, the clicking noise I'm hearing with the Duo Dock seems to be a power supply capacitor issue. Let's hope it is.

Took apart the PSU which required drilling out the rivets. What's interesting is that someone attempted to take the power supply apart as one of the rivets was already drilled out. But the other three were intact. Go figure.

My PSU doesn't have an SMD electrolytic on one of the daughterboards. It has a tantalum at that location instead. I guess that's good.

Cap list for the Duo Dock PSU. I don't see any other electrolytics inside the Duo Dock, at least on the one I have. Hope I didn't miss any.
  • C30, C28, C24: 100uF 25V 85C 6x11
  • C31, C6: 47uF 25V 105C 5x11
  • C35, C13, C10: 470uF 25V 105C 10x20
  • C9, C11, C17: 2200uF 25V 105C 13x39
  • C15, C25: 10uF 63V 105C 5x11
  • C4: 1200uF 10V 105C 10x23
  • C19, C12: 330uF 200V 85C 22x31
 
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