Wildlife Acoustics sm3bat, User Manual

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SM3BAT Setup SM3BAT User Guide
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BIOACOUSTIC MONITORING SYSTEMS
3.18.1
Details of Operation
The SM3BAT wakes up 150 seconds before a scheduled recording to give the GPS
time to acquire satellites. (Without the GPS option, the SM3BAT wakes up 30
seconds before a scheduled recording.) The recording starts within a fraction of a
millisecond of GPS time. If the GPS has been used recently in the area, the position
fix will take under a minute. If a significant amount of time has elapsed or the GPS
has been shipped some distance, the GPS must download new tables. In this case
the first position fix can take up to 40 minutes, but subsequent fixes should still
occur in under a minute.
While making the recording, the SM3BAT automatically makes small adjustments
by inserting or removing samples as needed to maintain synchronization with the
GPS clock to within one millisecond. Additionally, if recording to a .wac file, the
latitude and longitude coordinates are stored approximately every second. This
data can then be viewed with Song Scope or extracted by Kaleidoscope software.
NOTE : The GPS receiver does not synchronize recordings when using triggered WAV
mode. Synchronization is only provided for non-triggered WAV, non-triggered WAC,
or triggered WAC.
If synchronization was acquired and maintained for the duration of the recording,
the underscore character in the filename between the date and time changes to a
dollar sign as shown in the following filename examples:
ARIZONA-1_20160104_152209.wav
ARIZONA-1_20160104$152209.wav
This is how you can tell if the entire recording was successfully synchronized. If
the GPS signal was not successfully acquired before the recording started or was
lost at any point during the recording for more than a few seconds, the $ does not
appear in the filename.
3.18.2
Extracting Location Information
If the recordings are in .wac file format, location information can be viewed in
Song Scope (version 3.4 or later) by dragging the curser around the spectrogram.
If the recordings are in .wac or ZC mode and converted to .wav format in
Kaleidoscope, the GPS data can be extracted into either a comma-separated
values (.csv) file or Google .kml file. Select the Extract GPS track check box on the
GPS tab and select your format. The resulting file shows waypoints for the end of
each triggered event.
If you convert the recordings to zero crossing (ZC) format, the ZC file stores the
GPS coordinates. You can view them in compatible zero crossing software. If you
extract from .wac format, you can select a frequency in seconds to show path
information.