Unless you're planning on using the Apple Magic Trackpad with your laptop, it's hard to try and find reasons why this new peripheral can only use batteries. It's true this use of batteries is wasteful, and a USB-version would be much more appropriate. Until Apple comes up with this option, you can always hack your Magic Trackpad.
For now, Apple has neglected a wired version of this device. Markbog decided to convert his new trackpad so that it could run off USB power. It's a must for any desktop peripheral, although with USB ports few in between, maybe batteries make sense in some cases.
This is a very simply hack that requires a wooden dowel (cylindrical piece of wood that will fit in the trackpad's battery compartment). The dowel needs to have screws on each end. You'll also need some USB cord adn spare wire. First up, remove the batteries from your trackpad. Then, strip the USB cord down to the red and black wires. Attach them to the dowel and you're done!
USB power supplies 5V, which is more than the 3V 2 AA batteries provide, but it seems that the trackpad is able to regulate this power. There hasn't been an indication of it malfunctioning yet. While this trick seems to work well for the Magic Trackpad, we'd be careful about using it for other peripherals without adding some resistors or ways to modify the intensity of the USB current. You can end up bricking your device if the USB delivers too much power for it to handle.
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Comments (2)
I think all Apple products are going the way of wireless/bluetooth. Why not just buy rechargeable batteries so you aren't wasting as many? We are slowly converting to a completely rechargeable household and while the initial expense is more than that of regular batteries, the end result means less batteries in the land fill and more money (in the long run) in our pockets.
Rechargeable batteries are still WAY less efficient than direct power.
I guess what I don't get is why this is wireless to begin with. Most won't use it with their Macbooks because it has a built-in trackpad already, and if you're using it with a desktop PC, what's the point of wireless? You don't even need to move it around like a mouse (which can get annoying with wire attached, especially on a messy desk). It's sort of an all around strange product I guess.
I would like to see a wireless keyboard/trackpad single unit combo for use with a media PC - I can see that being very handy. Most of the existing options are pretty dreadful looking.