Agilent Technologies Signal Analyzer N9030a - Manual (Page 830)

6 RLC Swept SA Measurement Front-Panel & SCPI Reference
Meas Setup
Preset Off, –3.01 dB
OFF
State Saved The on/off status and the offset value are both saved in instrument state.
Min –140 dB
Max –0.01 dB
Backwards Compatibility
Notes In ESA, N dB points paid attention to the peak excursion and peak threshold set in the Search
Criteria menu under Peak Search. This is not the case in the X-Series.
In ESA, an invalid N dB reading was indicated, both onscreen and remotely, with a value of –100.
In the X-Series it is indicated on screen by --- but remotely still by –100 Hz
Initial S/W Revision Prior to A.02.00
N dB Points Results Query
Remote Command :CALCulate:BWIDth|BANDwidth:RESult?
Example :CALC:MARK:AOFF Set selected marker to 1
: CALC:MARK:MAX Put marker 1 on peak
:CALC:BWID ON Tturn on N dB for the selected marker (1)
:CALC:BWID:NDB–3.01 Set the offset to –3.01 dB
:CALC:BWID:RES? Query the result
Notes –100 returned if invalid reading
Initial S/W Revision Prior to A.02.00
More Information
A marker should be placed on the peak of interest before turning on N dB points. The N dB points
function looks for the two points on the marker’s trace closest to the marker’s X Axis value that
are N dB below the marker’s amplitude, one above and the other below the marker’s X Axis value.
(That is, one point is to the right and one is to the left of the selected marker.) The selected N dB
value is called the offset. The function reports the frequency difference (for frequency domain
traces) or time difference (for time domain traces) between those two points.
Each point is identified by a horizontal arrow pointing towards the marker, next to the trace. The
arrows used by the N dB Points function will be as shown in the figure below (where each square
represents one pixel). They point in, horizontally, at the trace below a peak, on either side of its
830 Remote Language Compatibility Measurement Application Reference