Battery Pack Power While Continuing to Use Garmin 705
 

I'm also interested in using batteries with my Garmin 705 but I want a battery powered 5V supply that will allow me to continue using the 705 while it is running off of battery power in case I run out of charge before the end of a long trip. When I put either my wall wart charger or my USB cable into my 705, it goes into a charge only mode and I can't use the GPS. Anyone know if any of the battery powered 5V supplies will allow you to continue to use the GPS while the external battery pack is connected to the USB port of the 705? Also, does anyone know where (website) there might be some specific information that describes what has to be done (pull up resistors on the data lines, no resistors on the data lines) to the USB connection that allows the 705 to continue to operate while it is being externally powered?

Currently I am using Radio Shack's iGo:

http://www.radioshack.com/search/ind...ype%2FChargers

Good quality. Seems to work well, wringing every bit of energy out of the batteries. Before this I used the Energizer 2xAA charger, which is a piece of crap. For the iGo you do need a mini USB tip, but when I bought it they had some sort of sale where I got a free tip. The only downside is the lack of a cable. I ordered a separate mini USB to mini USB to be able to plugin my Garmin while locating the charger somewhere else.