Keysight N9927-90001 User’s Guide                                                            227
RTSA (Real-Time Spectrum Analyzer) Mode—Option 350 (CPU2 Only)
RTSA Mode Settings
RTSA Mode Settings
Select RTSA Mode before making any setting in this chapter.
Because there is no calibration, these settings can be made in any order.
How to select RTSA Mode
—Press Mode_ 
—Then Real-Time SA
.
Frequency Range
The X-axis frequency range determines the frequencies that are measured for 
each sweep. The default Start frequency is 995 MHz. However, the Start 
frequency can be set as low as –100 MHz. The internal LO of the FieldFox can 
be seen at 0 Hz, which will mask signals that may be present. 
The frequency range of the measurement can be changed using the following 
methods:
— Set Center and Span frequencies (Freq Span is settable from 280 Hz to 
10 MHz)
— Set Start and Stop frequencies
— Using Marker -> Center
How to set Frequency Range
—Press Freq/Dist. 
— Then choose from the following:
When you initially select I/Q Analyzer, Real-Time SA, or some of the other 
spectrum settings (such as center 
frequency) a factory channel Equalization 
measurement is applied to the signal. During channel equalization 
measurement, the FieldFox displays a "Start Channel Equalization". 
Stopping channel equalization is not permitted. See also, “Alignments” on 
page 180, in Chapter 9, “SA (Spectrum Analyzer) Mode.”
Although the start frequency can be set as low as -100 MHz, amplitude 
accuracy is specified above 9 kHz to 100 kHz (depending on your model).  
Below 9 kHz to 100 kHz (depending on model), frequency accuracy is 
maintained, but amplitude accuracy is degraded. Refer to 
http://literature.cdn.keysight.com/litweb/pdf/5990-9783EN.pdf.
The FieldFox can be used with an OML frequency extender. Refer to 
“Utilities” on page 630, the A Series FieldFox Configuration Guide 
5990-9836EN, and to “Contacting Keysight” on page 5.