HP E4418B Programming Manual page 74

Power Meter Remote Operation
Setting the Range, Resolution and Averaging
Filter Length
You specify the filter length using the following command:
[SENSe[1]]|SENSe2:AVERage:COUNt <numeric_value>
The range of values for the filter length is 1 to 1024. Specifying this
command disables automatic filter length selection. Increasing the value
of the filter length reduces measurement noise. However, the time to take
the measurement is increased.
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