Quick Power Supply for a Macbook G4
This is also useful if your stuck in the congo, and need to power a macbook g4 off of 2 jeep batteries and hack apart a mini cell phone ear piece for power. Jack Bauer approved.
||Build & Test||Conclusion||Image Directory|
|Simple 3/32nd in audio jack||About
size as an apple legit power jack internal plug
only moderately over priced at your local radio shack
Probably the most ridiculous use for the 3/32nd size, 2A over a mini headphone size cable, If apple ever goes into power engineering i'm leaving.
|Here is another image of the connector, next to a small battery for scale|
|Multmeters||ammeter / voltmeters are very useful, but not necessary|
|Crufty Power Supply||24v,
~2A power supply. i found this
crufting years ago, it was for a childs scooter, probably a charger.
After scoping the outputs, i found that with the addition of 100uf of
output capacitance it was clean enough for me to try it out on the
macbook. As the current output is less than optimal, i let the macbook
charge before attempting to boot. if the macbook attempted to charge
quickly while booting it would possibly brown out the power supply.
Even if you only have a 24V 1A supply, use it to charge the laptop batts, (leave it pluged in with the laptop off), you could boot from the internal batts later on
If youve got access to a varable power supply that can do 2 A use it (like this one)
People who worked on this project:
(EE/ soldering / OS stuff)
Found the mac, helped out alligator-clipping / finding screws / generating ideas
Rensselaer Polytechnic Institute
Electrical & Electrical Power