[1] Read the manual and / or product specs.
[2] Try the different sample rates available and see which you prefer.
[3] Record with full batteries and see how long it runs.
Alternatively:
[1] According to
NomadWorld's feature list, it records in WAV:
1 stereo minijack line input for direct stereo audio recording in WAV format from external devices
[2] Record to 44.1kHz if you don't want to resample for CD, or 48kHz if you want to squeeze out a bit more quality for archival purposes and then resample to 44.1 for CD usage.
[3] No idea how long the batteries last, but safe bet is substantially shorter than advertised by the manufacturer.
Most folks here have experience with the JB3, so...curious to see if anyone will have solid answers. As noted above,
NomadWorld is a good resource, and
Nomadness is an even better resource for all things Nomad related.