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Any changes made to existing profiles that are saved, will be kept in the detector until it is
turned off. If you wish to permanently save a certain profile, please use the method with
externally generated profiles instead. Please refer to the section about the D1000X Utility for
information on this.
•
Recording mode
The recording mode is either manual (MAN) or automatic (AUTO). In the manual mode, the
user starts (and in some sub-modes also stops) the recordings by pressing the desired
recording key, usually the MIC key. In the automatic mode, the detector “listens” for signals
and starts a recording only in the presence of a signal that meets certain triggering criteria. In
the AUTO mode, the detector can be left unattended for automatic recording of bat calls.
More information on this is found in the section “The details of the triggering parameters”.
•
Sampling frequency
The sampling frequency (or sampling rate), f
s
, determines the maximum signal frequency that
can be recorded. The theoretical upper signal frequency limit is half the sampling frequency.
In practice, the upper signal frequency limit is lower than that. The D1000X has an adaptive
anti-aliasing filter that allows aliasing-free sampling up to about 0.4 x f
s
. This filter is
automatically adapted according to the chosen sampling frequency and does not require any
action from the user.
A higher sampling frequency gives better sound quality at the expense of larger sound files,
so it is usually a good idea not to choose an unnecessarily high sampling frequency. The
following sampling frequencies are available in the D1000X:
32, 44.1, 48, 96, 100, 192, 200, 250, 300, 384, 400, 500, 750 and 768 kHz
Note: In order not to interfere with the continued streaming of samples to the CF card at high
sampling frequencies, the update and display of the tuned frequency and the clock as well as
the update of the battery indicator is disabled while recording with the two highest sampling
frequencies, 750 and 768 kHz.
•
Time expansion factor
When replaying recorded sound files (either immediately after the recording was made – with
the Replay mode set to AUTO - or at a later time) the time expansion factor (TE) determines
how much longer the replay takes compared with the original signal. If the TE factor is set to
10, the replay will take 10 times longer than the original signal and the frequencies will be 10
times lower than they originally were. The TE factor only affects the D1000X playback, not
the resulting sound files.
Files recorded with the COM, HET or FD keys will obtain a TE factor of 1, regardless of the
TE value in the recording profile.
