Setting Data Markers - Symmetricom 5120A Operation And Maintenance Manual

If the mouse has a wheel, the equivalent of the Shift Up 1 Div and Shift Down 1 Div softkey
functions for the y axis can be performed by scrolling the wheel. Note that this operation puts the y
axis into fixed scale mode.
The mouse can quickly auto scale both the x axis and y axis. Right-click on the plot and select
Scale > Auto Scale. This function can be invoked by pressing the 'A' key on a USB keyboard.

5.1.2 Setting Data Markers

Data markers designate two specific frequencies, each with a diamond on the screen. These are
referred to as the marker and the delta marker. Once markers are positioned on a frequency, they
continue to display the measurement at that frequency until they are repositioned.
Both markers display their frequency and power spectral density values at the top of the phase
noise plot screen. This is useful because it provides more accurate coordinates than the plotted data
itself can indicate. The coordinates are updated as markers are repositioned or trace a new
measurement at their designated frequency.
When both markers are positioned, the difference between their coordinates is calculated and
displayed.
When either marker is tracing a measurement that is part of a spur, a small color coded window
pops up to indicate the spur's frequency and power. The power displayed in the window should be
used to determine the power level of the spur, as the graphical display is displaying the spur on a
dBc/Hz scale. The spur information window moves to another quadrant if the plot is scaled so that
the marker indicator collides with the window.
A placed marker is considered visible even if the plot is scaled so that its indicator falls off the
screen. A visible marker's spur information window remains visible as a result. When you Hide
Markers, their indicators and any extra window are hidden as well. Any extra windows visible at
the time the phase noise plot is printed will appear on the printout. Note that the marker
coordinates at the top of the screen overlap the title as a result of limited screen resolution.
Printouts have a much higher resolution and the marker coordinates are printed below the main
title instead of obscuring it.
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