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How to Set the Averaging Time
How to Set Automatic Gain for Averaging Modulated Signals
How to Choose the MinMax Function
How to Use External Triggers
Keysight N774-C & 8162-C Series User's Guide
This is the length of time over which a signal is averaged to produce a
measured value. Longer averaging times increase the accuracy and
improve the noise rejection.
The averaging time of the N774-C instruments can be set over a wide
range from 1 μs to 10s. Up to 2 ms, the setting can be varied with a typical
resolution of 2 μs, and for higher averaging times the setting resolution is
about 0.1%. This flexible setting time supports optimal synchronization
with the time scale of the signals. The high sampling rate with short
averaging times is supported by the high cutoff frequency, as shown in the
specifications. These bandwidths are reduced in steps, when longer
averaging times are used to improve the noise performance while
maintaining signal fidelity.
A fast Auto Gain switching is used to achieve the high dynamic range in
the N7744C and N7745C. In some applications, like determining the
average power of signals modulated with periods shorter than the
averaging time, this switching produces irregular readings. In such cases,
the Auto Gain should be turned off, as described in the N774-C
Programming Guide. This setting takes effect after setting the averaging
time on the port directly or via function parameters.
MinMax function measures the incoming power and returns the minimum
value measured and the maximum value measured of the selected
channel. Note that this measurement is independent from the graphical
plot. The difference between these values, delta P, is returned in place of
P, the power value.
This mode is intended principally for polarization dependent
measurements, but can be used for other types of measurement.
Reset MinMax - Use this option to reset the minimum value measured,
and the maximum value measured.
User Interface Reference
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