SA (Spectrum Analyzer) Mode
97
When the Res BW/Video BW ratio exceeds 10,000, a
Meas UNCAL
warning may
appear to indicate that the Video BW filter has reached the maximum capacity
for averaging.
In Zero Span, the maximum Res BW/ Video BW ratio is 100.
Sweep Type
In SA mode, the FieldFox uses two sweep types to process inputs signals. The
sweep type that is currently being used (
FFT
or
Step
) is displayed in the lower-
left corner of the FieldFox screen.
For a more comprehensive tutorial, see Spectrum Analysis Basics (App Note 150)
at
http://cp.literature.agilent.com/litweb/pdf/5952-0292.pdf
How to set Sweep Type
Press
BW 2
.
Then
Advanced
Then
Sweep Type
Then choose from the following:
o
Auto
The FieldFox selects the most efficient sweep type based on the Res
BW. When Res BW is set to 200 kHz and below,
FFT
sweep type is selected.
Above 200 kHz,
Step
sweep type is being performed.
o
FFT
The FieldFox uses FFT sweep type regardless of the Res BW.
o
Step
The FieldFox uses Step sweep type regardless of the Res BW. This is
useful for capturing impulsive noise that may be generated from nearby
electrical equipment.
IF Output
The FieldFox IF (intermediate frequency) can be output for external signal
processing. The signal is available from the IF Out connector on the FieldFox
right-side panel. See the connector on page 17.
The IF Out signal, centered at approximately 33.75 MHz, is simply a down-
converted version of the RF Input signal that is present at the tuned frequency.
While outputting an IF signal, the FieldFox stops performing the InstAlign
process. Therefore, the amplitude of traces on the FieldFox screen is NOT
accurate and
Meas UNCAL
appears on the screen to indicate this. Learn more
about InstAlign on page 107.
Learn more about the IF Output frequencies and bandwidths in the
http://na.tm.agilent.com/fieldfox/help/FieldFox.htm
How to select IF Output
The IF Output signal is useful only in Zero Span. Learn more about Zero Span on
page 99.
At least one sweep must be made in order to tune the FieldFox.
Press
BW 2
.
Then
Advanced
Then
IF Output Use