Use Of Generator Trigger; Use Of Manual Trigger; Use Of Averaging; Use Of Exponential And Linear Averaging - BRUEL & KJAER 2032 Instruction Manual

9.13.3. Use of Generator Trigger
When the 2032 Generator is set to Pseudo-random or Impulse output, Generator Trig-
ger should be selected. This will ensure that all data collection on the 2032 is synch-
ronised with the Generator output, taking account of the Delay after Trigger and Delay
between Channels set.
9.13.4. Use of Manual Trigger
Manual triggering is achieved by pressing the MANUAL TRIGGER pushkey, whereby
the 2032 will be triggered in accordance with the Delay after Trigger and Delay be-
tween Channels fields. Note that the MANUAL TRIGGER pushkey can be used in all
Trigger modes, whether or not Manual Trigger is selected.
9.14. USE OF AVERAGING
9.14.1. Use of Exponential and Linear Averaging
Note that Exponential and Linear Averaging apply equally to Spectrum Averaging, Sig-
nal Enhancement, and Amplitude Probability modes. The averaging algorithms involved
are given in Section 13.3.
9.14.2. Use of Peak Averaging
Peak Averaging is only allowed in Ch.A or B Spectrum Averaging. When Peak Averag-
ing is employed, the maximum value appearing in each line of the Instantaneous Spec-
trum over the selected number of averages is stored in the Peak Averaged Spectrum.
Note that in earlier BrOel & Kjcer analyzers, Peak Averaging has been referred to as
Hold Max. or Max. Hold.
9.14.3. Use of Averaging Overlap
When the 2032 is set to Spectrum Averaging and Free Running Trigger, the Averaging
Overlap can be selected to be 0%, 50%, 75%, or Maximum*. 0% means that only
statistically independent spectra are averaged, while 75% ensures, (real-time frequency
permitting) that when Hanning weighting is used the combined weighting functions for
the overlapping records will give an overall flat time weighting in a power sense. Maxi-
mum means that all spectra produced by the 2032 are averaged.
9.14.4. Calculation of Errors
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When calculating the errors associated with a measurement, it is important to know
the number of statistically independent results which have been averaged. When 0%
Overlap is employed, this can be read directly from the Number of Averages field on
the 2032 Display. When other Overlap settings are used, the number of statistically
independent averages will have to be calculated according to the selected frequency
span, the weighting function in use, the real-time frequency, and the duration of the
measurement.
* Or user-defined, see Section 12.5.3