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JazzCatDRP · 12:09 AM

Hey all,
so I've been working relentlessly on a huge school project due this Monday on my old Lombard G3 powerbook, when I suddenly got the "working on reserve battery power" warning. I checked the connection with my AC adaptor, and all was fine. I saved and shut the PB down to avoid any problems. Then upon thinking about it I remembered that earlier today I had a similar problem, but wiggled the connection and all was fine. I've tried it in different outlets, and it seems something's dead. Is there any way to tell if it's the AC adaptor that's dead, or something in the PB? I don't live within several hours of an Apple store. Is it possible at all to find an AC adaptor for something that old at a generic computer store? Basically, am I completely screwed to have a solution in time to finish my project before Monday?

jdiddy · Apr 16, 2005, 12:14 AM

Originally Posted by JazzCatDRP

Hey all,
so I've been working relentlessly on a huge school project due this Monday on my old Lombard G3 powerbook, when I suddenly got the "working on reserve battery power" warning. I checked the connection with my AC adaptor, and all was fine. I saved and shut the PB down to avoid any problems. Then upon thinking about it I remembered that earlier today I had a similar problem, but wiggled the connection and all was fine. I've tried it in different outlets, and it seems something's dead. Is there any way to tell if it's the AC adaptor that's dead, or something in the PB? I don't live within several hours of an Apple store. Is it possible at all to find an AC adaptor for something that old at a generic computer store? Basically, am I completely screwed to have a solution in time to finish my project before Monday?

Do you have another computer? Go to the local computer store pick up a 2.5 USB enclosure and pop the hard drive in there, then see if your other system reads it. That would be the easiest solution to get back your work.

JazzCatDRP · Apr 16, 2005, 12:16 AM

Thanks for the reply. Unfortunately, my other computer (this one) is a Windows machine.

roadracr · Apr 16, 2005, 09:09 AM

As you mentioned, first you need to understand whether the problem is with the computer or the AC adapter. The simplest way is to use a volt meter across the leads coming out of the AC adapter. For the Lombard AC adapter, the voltage reading should be between 21 and 24 volts. If it is much less, or zero, then the problem is the adapter. This assumes you can find somebody with a simple volt meter (you can get a real basic one for about $10.00 at Radio Shack). Granted, we are not testing the load capacity from the AC adapter, but this a quick test.

Asuming it is the adapter - and asuming you want to get a bit brave - you need to fabricate a makeshift AC adapter by purchasing a DC power supply (or, since you are in school, find a student in one of the science labs to lend you one). The AC adapter needs to be able to source sufficient current (amps) at the required voltage. In this case, the spec's for your Lombard power supply are 1.9 amps at 24 volts DC. This is not trivial and you will probably need to find an adjustable power supply that is far larger than your small AC adapter.

Again, assuming you have gotten this far and want to go forward, you then need to cut off the end of your AC adapter, leaving enough wire to connect it to the DC power supply. You will need to know which contact is positive (+) and which is ground (-). This is VERY important as you DO NOT want to reverse the two. The end of the connector looks like a protruding center pin surrounded by a metal shield. The protruding center pin is the positive (+) contact and the shield is the negative (-) contact. You will need to strip the wire leads from the adapter cord and use an ohm-meter or continuity tester (the cheap volt meters can usually perform this function as well) to determine which wire leads to the center pin and which leads to the grounding shield. You then connect the positive (+) wire to the positive (+) output on the DC power supply and the ground (-) wire to the negative (-) output on the DC power supply. That will give you a temporary power supply to get you through the weekend.

Not sure most people would want to do this, but you said you were desperate. Good luck.

amazing · Apr 16, 2005, 10:47 AM

Do you have a CompUSA or perhaps an Apple Service provider nearby? Take your Lombard in and hook it up to one of their PB power supplies. If it works, that's what you need. Alternatively, would a nearby friend have a PB that you could test their power supply with your Lombard?

All you have to do is power up the Lombard long enough to either burn a cross-platform CD of your Doc.

wuzup101 · Apr 16, 2005, 12:21 PM

Go make friends with one of the professors in your school's electrical engineering department... and bring him roadracr's post. I know the few Drs that I know in the EE department could do that in all of 10 min

. Actually sounds like a very viable work around if you're desperate. I personally would also consider buying a 2.5" external enclosure. Surely your school's computer lab has some powermacs or imacs that you could work on for the time being???

DeathToWindows · Apr 16, 2005, 06:03 PM

yeah, i'd go with the �bergeeky option given above... a nice bench supply

JazzCatDRP · Apr 16, 2005, 06:33 PM

Thanks for all the help folks. I spoke to my professor today and she's granted me an extension, so I have a little more time to figure something out now. I purchased a voltometer, but am unsure how exactly to test it. I tested the first half of the cord (the part that plugs into the wall outlet to the part that plugs into the brick. That part was fine. The second half of it didn't register at all though. That would make me think that's the problem, but I'm not sure if I'm testing it right. Does it matter if I have the meter touching the inside part of the plug (the end that plugs into the PB). Also, exactly what setting would I use to test that part of the adaptor...I know jack squat about electricity and all that entails.

spiff72 · Apr 17, 2005, 05:16 PM

I hope we don't read about someone being electrocuted in the next day or two...

If you were checking the power of the part that connects to the wall (a bit scary if you don't know what you are doing), you would be measuring AC, rather than DC. The output of the brick would be DC, so you might have to change the setting of your voltmeter to read DC rather than AC. If you didn't do that, I wouldn't write off the power brick just yet.

JazzCatDRP · Apr 17, 2005, 08:41 PM

Yeah, I hope you don't read about me being electrocuted either!

Testing the power brick on DC registered nearly nothing. Once I got it to jump from 0 to .01, but that was it. Anyway, I've got both an AC adaptor and a power/sound board coming my way from eBay...whichever I don't need I'll re-sell.

Here's a quick question. It had been my understanding the power adaptors die pretty suddenly. I had the experience earlier in the day with needing to wiggle the power adaptor's connection to the laptop to get it to register that it was connected...would that lend any evidence to the fact that it may be the power board? Or can power adaptors slowly die?