Ok, I am impressed. Really impressed. This week I decided to make ladyada's Minty Boost, a portable USB power pack that will charge your iPod, takes 2 x AA batteries, and fits in an Altoids gum tin.
Why would you make the Minty Boost? Because you turn into a spider monkey on acid the moment your USB-powered mp3 player dies and you can no longer ride with tunes. Stick a Minty Boost in your seatbag, and put your mind to rest, since now you will not have to get to a USB connection on a computer to restore the power to your player. Plug in your dead iPod and pedal away in happiness. The Altoids tin is a great size for stashing in a jersey pocket.
These photos taken by Wheelgirl
(*Deep Thought: Put the earbud in only one ear. Listen to your music on low, so you don't get pressed. And unless you are trying to win a Darwin award, think about why you don't want to listen to loud music through noise cancelling headphones while on the road.)
ladyada studied some of the other USB portable battery packs, and she designed this pack a while back, in part because it is smaller, lets you listen longer, and doesn't have an on off switch that you can leave on by mistake. Her documentation on her design process and the kitting up of an original electronic design is a good read for you gearheads.
ladyada finds the Altoids gum disgusting, and her design has a 5V boost converter that facilitates a big power boost. This, in turn, gives you more more hours of listening time from your 2 x AA batteries. And the battery drain with her design is so teeny, it would take about as long as the life of the batteries for all of the power to leech out. Here are running time numbers taken from her site:
- "iPod video (tested, using alkaline batteries): 3hrs more video (1 full recharge)
- iPod shuffle (not tested): 60 hours more (5 full recharges)
- iPod mini (tested w/rechargables): 26 hours more (1.5 full recharges)"
ladyada sells her kits on her retail site, adafruit. And her documentation, photos, and specific attention to detail provide for a great electronic hobbyist experience. She did her grad work at MIT and has designed some other dandy electronic devices for bikes. If you have questions related to your specific device, there is a user forum where you can ask questions.
Go click around on her site even if you hated math and just wanted to write short fiction and smoke cloves when you were in high school.
All detailed photos taken from ladyada.
