Electronics Infoline Web

DIY iBook or Powerbook External Battery

The idea here is to have a large battery pack, a regulator to keep the voltage constant at 24V (should be able to handle at least 1.5A continuously), and a male 2.5mm stereo headphone connector (same as the typical cell phone hands-free connector), which fits the proprietary Apple power connector.

http://kc0wys.homeunix.com/projects/electronics/05/index.html

Using AT Type Computer Power Supplies

AT type computer power supplies are often used by model railroaders to provide 12 and 5 Volt accessory power for their layouts. These supplies are reasonably inexpensive due to their age and have been removed from old personal computers.

http://home.cogeco.ca/~rpaisley4/ATpsu.html

13.8 Volt 15 Amp from a PC Power Supply

Depending on the PC model, these are rated anywhere between 150 and 240 W. For supplying socket 7 main boards they have four different output voltages of +5 V, +12 V, -12 V and -5 V.

http://www.qrp4u.de/docs/en/powersupply/