NARDA ELT-400, Руководство по эксплуатации

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5 Operation and use ELT-400
5-14
5.4 Active probe (using the three-channel analog output)
The signal detected by the field probe (measurement coils) can be displayed
for scientific applications or further analysis of the signal shape and
frequency. An oscilloscope or FFT analyzer can be connected to the analog
signal output (Scope) of the ELT-400 for this purpose.
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External connectors: see page 4-6
The analog signal output provides the signal voltages for all three spatial
axes with their correct phases and covers the entire bandwidth of the
instrument. The output is also affected by the measurement range,
operating mode and lower frequency range limit settings.
If the measurement is to be referred to the spatial axes, the probe must be
aligned to correspond.
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Annex D: Probe configuration / signal output: see page D-1
The analog output can be used in both modes (Exposure STD and Field
Strength).
The maximum output voltage of 800 mV RMS equals in each case the scale
end value of the selected measurement range. The impedance of the output
is 50 Ohm. A minimum load impedance of 10 kOhm is required.
Slight DC offsets can be present at the output. We recommend that you
measure with the oscilloscope or spectrum analyzer in AC mode.
Note the following (depending on the measurement mode):
Field Strength mode
The output voltages at the X, Y and Z outputs correspond in each case to
the measured field strength (magnitude and phase).
Exposure STD mode
The magnitude and phase of the output voltage vary relative to the field
strength due to the transfer function in Exposure STD mode (the phase
relationship between the three channels X, Y, Z is unaffected).