3 Spectrum Analyzer Mode
3.2 Swept SA Measurement
Zoom Span is directly coupled to Zoom Points. If Zoom Points changes, Zoom Span changes but
Sweep Points does not
Preset On entry to Trace Zoom, 10% of the number of points in the upper window
State Saved Saved in instrument state
Min 1
Max Number of points in top window
Annotation On second line of annotations, in bottom window, in lower right corner in parenthesis behind the
sweep annotation
IF Dithering
Lets you turn IF Dithering on or off. This is a technique used in unpreselected
instruments (such as Keysight’s modular instruments) to enhance the rejection of
images and internally-generated spurious signals.
Remote Command
[:SENSe]:SWEep:IF:DITHer OFF | ON | 0 | 1
[:SENSe]:SWEep:IF:DITHer?
Dependencies Only appears in SA Mode in VXT
Grayed-out in Zero Span
Preset
OFF
State Saved Saved in instrument state
The image below shows the results of dithering for a 2.5 GHz span centered on 5
GHz. From top to bottom, the traces show the following: the captured signal after
standard image rejection has been applied, the low-side measurement, the high-
side measurement, and the final result after dithering and image rejection. Although
it is probably impossible to completely eliminate the chances of a false response on
the display, enabling randomized IF dithering and minimum-hold across a few
display updates will, for all practical purposes, ensure correct results.
Spectrum Analyzer Mode User's &Programmer's Reference 503