Hello Matt: I wouldn't recommend using any kind of non Humanware approved charger as the voltages, amperage and polarity are very specific for the BrailleNote family and you can void your warrantee by using a non-approved charger.
A lot of us have been asking Humanware for some kind of Universal power source or external battery and I think they are working on it, but nothing yet. I'd suggest you call Humanware in California and get a second charger if you can't get access to your regular one. hth Jeff
