114                                                                                                                     Keysight N9938-90003 User’s Guide
SA (Spectrum Analyzer) Mode (Option 233–Mixed Analyzers)
SA Mode Settings
— Then choose from the following:
—Center Channel
 Places the center frequency of the specified channel 
in the middle of the X-axis. 
—Start Channel
 Places the lowest frequency of the specified channel at 
the beginning of the X-axis. 
—Stop Channel
 Places the highest frequency of the specified channel at 
the end of the X-axis.
—Freq Span
 Changes the span of frequencies while the center frequency 
remains unchanged.
—Follow each of the above settings by entering a value using the 
numeric keypad or the rotary knob. 
—Use the   arrows to increment the channel number by an amount 
specified by the Channel Step value (see below).
—Then press Enter
 or Enter. 
Select either Uplink or Downlink Frequencies
Press Freq/Dist then More. Press Chan Direction to toggle between Uplink 
and Downlink
. If either of these selections is not available, then the selected 
Radio Standard does not contain those frequencies. In that case, Chan 
Direction is grayed out.
Channel number X-axis annotation
— Dn indicates Downlink channels. 
— Up (not shown) indicates Uplink channels
— (−) indicates that the lowest frequency in the channel (128) is at the left 
edge of the screen. 
— (+) indicates that the highest frequency in the channel (130) is at the right 
edge of the screen. 
Integration BW (IBW) is coupled to the Frequency Span setting. Frequency 
Span is 50% wider than the IBW (e.g., if the IBW value is 1 MHz, then the 
Frequency Span value is 1.5 MHz).