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2300c Duo Adapter Alternatives?
Posted by: LCARS on 2022-02-04 15:11:07
Somehow I have misplaced the adapter to my 2300c. I've spent hours looking for it and found the duo (hah, clever) battery charger clip-on but not the actual adapter. I haven't given up hope but I thought I might try to find alternatives just in case.

I see that the 2300c requires 36 watts and 1.5 amps. I do have a 2400c adapter with 36 watts but 1.8 amps. Can I safely use the 2400c adapter with the Duo?

Any known-safe generic alternatives? Or...anyone have a spare?
Posted by: 3lectr1cPPC on 2022-02-04 15:25:57
Using the 2400c's adapter should be fine. The computer will only draw as many amps as it needs, and the rest just won't be used. The 1.8 amp rating just means that that is the limit it can supply, it will only supply that amount if the computer requires it.
Posted by: Johnnya101 on 2022-02-04 16:17:02
Agree with above. Such a small difference won't matter. As long as it's that rating or a little above you should be good.
Posted by: LCARS on 2022-02-05 06:45:25
Excellent to know. Thank you @3lectr1cPPC and @Johnnya101. I suspected that the computer would only draw what it needs but I would have really hated to be wrong and find out the hard way.

I've been determined to use that machine independent of its dock, despite the awful keyboard.
Posted by: LCARS on 2022-02-19 13:39:08
The 2400c adapter works perfectly. I did buy a replacement 1.5amp 2300c adapter...but it doesn't work (no hum, no warmth). The center pin feels loose but I don't have a multi meter here. Are the Duo power bricks known to fail?
Posted by: 3lectr1cPPC on 2022-02-19 16:23:52
Yes, I believe so. I've even heard accounts of them letting magic smoke out! Pretty much all of the old PowerBook adapters are known to go bad unfortunately. It's usually just caps luckily, so if you can get them open there is a pretty good chance you can get it running again. For yours it could obviously be a different problem as you described your pin being loose.
Posted by: LCARS on 2022-02-20 08:11:34
Thanks, @3lectr1cPPC. Not the magic smoke! I've never experienced that, actually. I had a "where there's smoke, there's fire," experience with a NOS Nubus ethernet card a few years back. The magic there was that my IIci wasn't ruined.

Sigh, I guess this has to go back. Comparing this pin to other adapters, it must be the culprit. I kind of wish it was just a capacitor. Although these bricks seem tough to open. Hair dryer and pry?
Posted by: 3lectr1cPPC on 2022-02-20 08:25:09
I believe it may be plastic-welded, at least, I've heard other PowerBook adapters use more than glue. People have had luck using a vice to get other PB adapters open without damage. Prying could work, but only if you're ok with damaging the plastics.
Posted by: mdeverhart on 2022-02-20 08:33:21
There are a couple of contacts on the side of the power adapter that you can test to see if it’s generating the proper output voltage (though it’s still possible that it won’t work properly when under load). The Service Source document for the Duo has details toward the end:

https://www.powerbook.micahgartman.com/ss/ss_200series.pdf
Posted by: glay78 on 2022-02-26 04:52:53
If I’m not wrong the following adapter are pretty much the same voltage and connector

PowerBook 3400c
PowerBook 2400c
PowerBook Duos
iBook G3 Clamshells
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