Agilent Technologies 35670A Manual page 161

CALCulate
You can also set the value with an expression. Send
CALC:MARK:BAND:STAR (CALC:MARK:X?) to set the value to the current X-axis marker value.
If the X-axis is in time, this command specifies the start time for computation of time domain parameters.
The default position is at the left edge of the trace.
The query returns the value of the current start frequency of the band (or the start time) in X-axis units.
The value is returned even if the band markers are not on.
To determine the X-axis units, send CALC:MARK:BAND:STAR? UNIT.
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