132                                                                                                                     Keysight N9927-90001 User’s Guide
Calibration for NA, CAT, and VVM Modes
not. Without extended cal, if you adjust your frequency outside the 
calibrated range after the calibration has been completed, the error 
correction is turned off. 
— OFF
 (default) The FieldFox does not measure any frequency points 
outside the current displayed frequency range. If the frequency is 
adjusted outside of the set of points calibrated the error correction is 
turned off and the following message is displayed:  
"Error correction disabled. Stimulus outside  
calibrated range."
—Press Start Calibration
. When prompted, verify the ECal module 
connection, then press Measure. The standards within the ECal module are 
automatically connected and measured.
Simple Response Cals 
Simple Response Cals are used to quickly calibrate the magnitude and phase 
of a measurement using any Open, Short, or Thru component. These may be 
calibration standards, but because a Cal Kit is not selected, they are not 
modeled. Measurement accuracy is generally low. Use a Simple Response Cal 
to make quick measurements when using a jumper cable to connect the DUT 
to the FieldFox. Otherwise, CalReady is usually more accurate.
When prompted, choose a standard based on the displayed measurements to 
be calibrated. For example, to calibrate S11, connect either an OPEN or 
SHORT to the port 1 reference plane. 
When Simple Response Cals are performed, the source match and reflection 
tracking terms from CalReady are updated by the measured Short or Open that 
is used during the calibration. 
1-port response cals are also available from the Mechanical Cal menu. Learn 
more in “Calibration Type” on page 134.
’Unknown THRU’: When prompted: “Connect port 1 to port 2", then 
connect port and port 2, using a coaxial cable or an appropriate thru 
adapter. Do NOT use the internal ECal THRU, because the ECal thru 
calibration model is incorrect for this calibration type.  
 
‘Flush THRU’: When prompted: “Connect port 1 directly to port 2", then 
you must connect the ports directly together at the calibration reference 
plane with no adapter or other cabling.  
 
Learn more in “Calibration Type” on page 134.
You can perform a Simple Response Cal for either: S11, or S22, or S21 AND 
S12.