Recapping PowerBook 100 Series 7.5v 2A AC Adapter

[eric]

This is for the 7.5v 2A version - M5140 (APS-20U) & M5651 (APS-20U) (and possibly others)

Opening the Adapter​

Using a flat head screwdriver, place it between the output cable and the top case. Press in hard till you hear cracking then rock it back and forth a bit. You shouldn't hit any components but it does take quite a bit of force to open.

Once opened there is one Philips screw near on the PCB near the plug end. It's a bit tricky to see. Unscrew and lift that side out first to slip the PCB out.

What to check​

Fuse​

Check the fuse while you're in here with a multi meter to ensure it is not blown.

Capacitors - M5140 (APS-20U) & M5651 (APS-20U)​

Pay attention to the size of the capacitors, the spacing is limited in the brick.

Main Board​

• C108 400v 47uf
• C201 16v 1200uf
• C302 16v 180uf
• C105 50v 47uf
• C207 16v 82uF

Daughter Board​

• C151 35v 33uF (orig 6.4x8, but only 5x11 available)
• C252 50v 1uF (~2mm taller than orig, should fit)

​

​

Capacitors - M5652 (APS-46U)​

RIFA - 0.22uf - 250v
C108 - 82uf 400v
C209 - 2200uf 16v
C211 - 470uf 16v
C111- 47uf 50v (hard to get a good angle on it to read)

I did not recap this one as it is working fine.

Corroded traces on back side​

Check the traces on the back. Clean any corrosion off and check the traces are good. You may need to add bodge wires if any are corroded so much they no longer create a connection.

Other Resources

• https://www.reddit.com/r/VintageApple/comments/hbzidj

 

[ScutBoy]

Nice - fixing a couple of these is on my "to-do" list. Good to have a guide.

 

[Androda]

@eric The links to capacitors C201 and C302 don't seem to be working. There appears to be a tinkerdifferent URL prefix (before the actual mouser link) which is likely the culprit.

And I'm pretty sure C201 is 1200uF, not 12000.

 

[Danny D]

Edit: I'll order one or two of the modules listed here to try and will post again stating how I go in the future: https://www.meanwell.com/productSeries.aspx?i=18&c=6#tag-6-18. I presume a 3" x 2" module would also fit and run cooler, however a 2A fuse would probably need to be added for protection on the PowerBook side. It would be interesting to compare efficiencies too. Now, where did I put my 165's adapter?...

 

[alxlab]

I agree with lausvi to use a vice to open the adapter. I was able to open my M5140 adapter using a vice without damaging the case. As you tighten the vice it makes the sides want to bulge out thus breaking the bond between the two halves of the adapter. Once one side is open, rotate and repeat.

It's also interesting that the M5140 has a pot to adjust the amperage. I was actually able to boost the amperage on mine from 2A to 3A so it would work with a 165C no problem. No excessive heat from the adapter so looks alright.

Wonder with the internals of the 2A and 3A adapter are exactly the same with just the pot dialed to give more amps?

Here's another guide I used to help repair mine:
https://goughlui.com/2016/09/19/repair-apple-macintosh-powerbook-100-ac-adapter-m5140x/

 

[pfuentes69]

What is the connector type for these adapters?
I'm getting a 145B without adapter and I think (please confirm) that it's 7.5V, minimum 2A and the barrel is positive in the center, but I don't know the type of barrel.
Does anyone know this?

 

[alxlab]

It uses a 5.5mm x 2.1 coaxial power connector that's roughly ~9.5mm long. See it pretty commonly on the 12V adapters I have.

 

[eric]

Updated cap list with ones I ordered and a photo showing all caps. I did recap mine and it works great, just over 7.5v.

 

[eric]

Added cap list for similar outside, but completely different inside M5652 (APS-46U)

 

[SteveHere]

Here's a YouTube video that demonstrates the vise method mentioned above. I've used this method successfully on a Macintosh Portable power supply M5136.

 

[The House of Moth]

Glad I found this, I have a box full of em that I want to save

 

[PL212]

It's interesting that a few folks (myself, Gough and this person) have measured 7.6v - 7.8v or so after a full recap. I've made the decision to leave well enough alone and not adjust the pot, under the assumption that there's a bit of loss through connectors and cabling and it's unlikely to harm anything. But I'm curious if anyone has tried to nail 7.5v exactly, or thinks its important?

 

[Daniel Hansen]

I haven't, as I was seeing exactly what you're seeing around the web. I suppose you could though, the Service Guide (https://vintageapple.org/macbooks/pdf/APPLE_MACINTOSH_SERVICE_GUIDE_VOL2_1992.pdf) says a good adapter reads between 7.5V and 7.9V.

 

[PL212]

Thanks - I think that cinches it! Now I feel confident gluing the case back together….