Agilent Technologies Signal Analyzer N9030a - Manual (Page 672)

6 RLC Swept SA Measurement Front-Panel & SCPI Reference
Marker
Setting or Querying the Marker Z Position
The command below sets the Marker Z position in the Spectrogram View only. Setting the Z
Position sets which of the 300 traces in the Spectrogram the selected marker will appear on. In
each case the marker that is addressed becomes the selected marker. It has no effect (other than
to cause the marker to become selected) if the control mode is Off, but it is the SCPI equivalent of
making a Marker Z entry if the control mode is Normal,Delta, or Fixed.
Remote Command :CALCulate:MARKer[1]|2|...12:Z:POSition <integer>
:CALCulate:MARKer[1]|2|...12:Z:POSition?
Notes The command sets or queries the Z Axis position. In the Spectrogram View, this value correlates
to be one of the 300 stored traces. Each Z Axis position represents a different stored trace.
Preset 0
Min 0
Max Number of traces stored is limited to 300.
Default Unit unitless
Marker Backwards Compatibility
In earlier Agilent analyzers, markers were position markers, which means that Normal and Delta
markers stayed at the same screen position when X Axis parameters were changed. So a marker at
center screen stayed at center screen even if Center Frequency was changed (which means that
the marker’s frequency changed). In the X-Series, markers are value markers, which means that
when the analyzer’s X Axis settings are changed, the marker’s X Axis value in fundamental X Axis
units remains unchanged. For example, if you put a marker at a particular frequency, it will stay
at that frequency regardless of whether or not you change the Center Frequency of the analyzer,
even if that means that the marker ends up offscreen.
While this change resulted in an overall higher level of usability of the marker system, there are
some use cases where the user depends on the marker staying at the center of the screen. The
most common one is where the user turns on a marker at center screen and uses it to measure the
trace amplitude at the center frequency or at a series of center frequencies, without the need to
ever move the marker. In the X-Series, to mimic the legacy behavior for this use case, the user
must turn the marker off and then back on after changing the center frequency of the analyzer.
This causes the marker to reappear in the center of the screen.
Also as a result of the change from position markers to value markers, markers can be at a
frequency which is offscreen, whereas in the past, they were clipped to the screen edges and
hence were never offscreen. Users who depended on this clipping behavior to force markers to
the edges of the screen will have to rewrite their code. Furthermore, since markers could never be
672 Remote Language Compatibility Measurement Application Reference