ladyada wrote:you can never go wrong with a 6V lantern battery :) stick a 1N4001 in series and boom, now you've got it down to 5.3V...safe for your arduino.
That's a nice simple idea. Thanks! A related question is, can I just attach the polarized power jack from my dead 9V battery holder to the battery/diode supply and plug it into the Arduino? I assume it's going to go through the 7805 if I do that, and I don't know whether to expect it to do anything wonky if it gets just 5V in.
Over in the Arduino forums, I just saw someone mention Rob Faludi's recent summary of Arduino battery lifetimes
- using different batteries, sleeping or not, without or without a XBee, ... He apparently got 178 hours from 4 2500mAh NiMH AA batteries, even without sleeping, vs only 19hours from a 2AA MintyBoost-type supply.