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The details of the triggering parameters
The manual recording mode
The manual recording mode is selected in the settings menu. In this mode, the recording is
started by pressing the desired recording key. In order to record the ultrasonic signal from the
microphone, press the MIC key and the recording starts. While the internal memory buffer is
being filled, the text ”BUFFERING” is shown on the display. As the memory buffer has been
filled, the text changes to “CAPTURE” and the detector waits for the “trigger signal”, which
in the case of the manual recording mode usually means pressing the MIC key a second time
(with some parameter settings, the system can also be triggered by the signal exceeding a
certain level). After that, the recording continues for a time equal to the value of the POST
parameter. The resulting sound file contains the time interval from PRE seconds before the
triggering moment and to POST seconds after the triggering moment. This is illustrated in the
figure below, where the PRE trigger time is 2 seconds and the POST trigger time is 3 seconds.
Note: The actual PRE and POST trigger time that is obtained may differ slightly from the
chosen value, depending on the PRE/POST values and the sampling rate. A low sampling rate
and/or a short PRE/POST value will increase the deviation.
Manual recording mode with PRE = 2 seconds and POST = 3 seconds.
If the POST time is set to OFF while keeping the PRE time as in the previous case, the
recording will be interrupted as soon as the MIC key is pressed the second time or a level
trigger is received as shown below.
time
Press MIC
Recording
starts
Buffering
Capturing
Recording
Press MIC
or
Level trig
Triggering
moment
PRE time (2 sec.)
POST time (3 sec.)
File beginning
File end
