Keysight x-series Programmer's Reference

3 VMA Mode
3.1 Digital Demod Measurement
X Reference
Chooses whether the limit line x points are fixed, or relative to center frequency
when x axis unit is Hz, or relative to trigger when x axis unit is time unit and trigger
source is not free run, or relative to sync pattern when x axis unit is time unit and
sync search is on.
For example, assume you have a frequency limit line, and the instrument center
frequency is at 1 GHz. If Relative to CF is “Off”, entering a limit line segment with a
frequency coordinate of 300 MHz displays the limit line segment at 300 MHz, and
the limit line segment will not change frequency if the center frequency changes. If
Relative to CF is “On”, entering a limit line segment with a frequency coordinate of
300 MHz displays the limit line segment at CF + 300 MHz, or 1.3 GHz. Furthermore,
if the center frequency changes to 2 GHz, the limit line segment will be displayed at
CF + 300 MHz, or 2.3 GHz.
It is possible to change this setting after a limit line has been entered. When
changing from On to Off or vice-versa, the x values in the limit line table change so
that the limit line remains in the same position for the current settings of the
instrument.
Remote
Command
:CALCulate:DDEMod:LLINe[1]|2|…|6:X:REFerence FIXed | RCF | RTRigger | RSYNc
:CALCulate:DDEMod:LLINe[1]|2|…|6:X:REFerence?
Example
:CALC:DDEM:LLIN:X:REF RTR
makes limit line 1 relative to the trigger
Notes Relative to CF is only available when x axis unit is Hz, otherwise it is grayed-out
Relative to Trigger is only available when x axis unit is time unit and trigger source is not free run,
otherwise it is grayed-out
Relative to Sync is only available when x axis unit is time unit and sync search is on, otherwise it is
grayed-out
Preset FIXed, not affected by Mode Preset, preset by Restore Mode Defaults
State Saved Saved in instrument state
Copy from Limit
Copies an existing limit into the current limit, including all secondary parameters
(Description, Comment, Associated Window, X Axis Unit, Y Axis Unit, X Offset, Y
Offset, Type, Margin, X Reference). The destination limit is specified as a
subopcoded LLINe parameter and the source limit is specified as a numeric
parameter.
Remote Command
:CALCulate:DDEMod:LLINe[1]|2|…|6:COPY 1 | … | 6
Example
:CALC:DDEM:LLINE2:COPY 1
383 Vector Modulation Analyzer Mode User's &Programmer's Reference

Keysight x-series Specifications

General

Analysis Bandwidth	Up to 1 GHz (depending on model)
Real-Time Bandwidth	Up to 1 GHz (depending on model)
Form Factor	Benchtop
Connectivity	LAN, USB, GPIB
Resolution Bandwidth	1 Hz to 10 MHz (depending on model)