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a) The ultrasonic signal
In this case, which is the typical and most common, any sound with a level exceeding the
trigger threshold (and meeting all other triggering conditions) will trigger the recording
system.
b) The output signal of the heterodyne system
This gives a frequency-selective triggering. Only signals that are audible from the heterodyne
system (i.e. signals with a frequency close to the tuned frequency) will trigger the recording
system.
c) An external trigger signal connected to the External Trigger Input jack (optional).
The jack is located above the Input Gain control on the front panel. This jack is an optional
feature and is not available on the standard version of D1000X. The signal terminal is the tip
and the ground terminal is the sleeve.
Connecting an external signal to the External Trigger Input makes it possible to control the
recordings externally. This is an analog input that follows the same level settings as the other
triggering sources. It can, however, also be used with digital signals. The trigger voltage is
between ca. 2.5 and 4 V depending on the setting of the trigger level. The detector triggers on
the negative-going edge of the trigger signal. A small delay from the negative-going edge to
the actual start of the recording may occur.
Caution. The level of the signal connected to the External Trigger Input must not be
lower than –0.3 V or higher than 5.3 V, referenced to ground, or damage to the
D1000X may result. No signal at all should be applied when the D1000X is
switched off.
•
High-pass filter enable/disable
The D1000X contains a high-pass filter at the input of the recording system. This is typically
used to attenuate undesired low-frequency signals and noise (below 20 kHz). The high-pass
filter can be disabled by setting the “HP” parameter to OFF.
•
LED/LCD background intensity
The intensity of the LED indicators and the LCD background light can be adjusted to the
desired level with the LEDINT parameter. Eight different levels are available, where 0 turns
all LEDs off.
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