The Fostex FR-2LE has the ability to carry a 7.2V RC Car battery
internally, in place of the standard battery sled that holds four AA
cells. Fostex says a 3600 mAh battery of this type should provide 8
hours of WAV recordings.
I received a 3800 mAh 7.2V RC car battery and charger from an eBay
retailer last week. The RC battery weighs more (340 g vs 160 g for
the standard AA battery sled), but it fits easily into the battery
To test the RC battery life, I set up the FR-2LE to record in 192Kbps
MP3 to a 4 GB Compactflash card. I started recording the household
ambience, and went about my business. 12 hours later, I was surprised
to find the recorder still actively recording. I saved the file and
continued recording. At the 17 hour mark I gave up and ceased
I shut down the recorder and transferred the Compactflash card to a
PC. At first I could see no files on the card, so I ran CHKDSK /F.
The program recovered two files. I renamed them to have the MP3
extension. At this point, Windows Media Player recognized the files
and had no trouble opening and playing them.
In my experiment, the FR-2LE ran for 17 hours and created 1.4GB of MP3
files. The battery still shows 3/4 full! Running from AA cells, I
don't get more than 4 hours.
Certainly it takes less energy to create a low bit rate file like
192Kbps MP3 than it does to record at 24/96 WAV. So I have more
testing to do.
At this point, though, I feel confident that that the 3800 mAh RC car
battery will easily power the FR-2LE for an all-day session in the
field. Thanks, Fostex, for adding this feature to the FR-2LE!