Agilent Technologies E4406A Using System Features, Using System Configuration and Alignment Keys

Using System Features

Using System Configuration and Alignment Keys

•Corrections - When set to On (the default state), the alignment firmware applies many numerical corrections to improve amplitude accuracy of the measurement. This includes an absolute amplitude adjustment at center frequency, and IF flatness correction for FFT spans (spectral measurements). When corrections are Off, the background alignments which determine corrections are disabled. Corrections is a background feature which runs automatically, while the instrument is on.

•Time Corr - Time corrections are the application of a complex filter directly onto the time capture data. It compensates for the complex (magnitude and phase) response of the analog and digital IF hardware. Time corrections are less efficient (take more CPU cycles) than frequency corrections when only scalar (magnitude) FFT flatness is required, but for demod or other time-based (not FFT) measurements, only time corrections can improve the flatness of imperfect IF hardware. If the time correction functionality is set to Auto (the default), the individual measurements activate the corrections when they are needed.

•Restore Align Defaults - Restores the instrument’s align defaults. This feature will only be needed if the instrument calibration locks up, which may occur as a result of hardware problems. Once the defaults are restored a message will appear informing you that alignment is needed.

•Visible Align - When toggled to Off, the alignment traces which are visible in the display during an alignment will be turned off, and the alignment process will take less time. When set to High, every alignment trace is shown, resulting in the alignment taking more time than when Visible Align is set to Low (the default state), where one out of ten traces is shown. Note that text showing alignment results is displayed on screen when any alignment is activated, even when the visible alignment is set to Off.

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