HP 8590 E & L Series Spectrum Analyzers and HP 8591C Cable TV ...

FFTMM
FFT Marker to Midscreen
FBTMM FFT Marker to Midscreen
Changes the FFT midscreen frequency of the spectrum analyzer to the frequency of the FFI
marker.
Syntax
FFTMM
Equivalent Softkey: M&lXER -) KID SCRN .
Prerequisite Commands: FFTAUTO, FFTSNGLS, FFTCONTS.
Related Commands: FFTMS, MKA, MKF.
Example
OUTPUT 718;"FFTCONTS;"
OUTPUT 718;"MKPK HI;"
OUTPUT 718;"MKPK NH;"
OUTPUT 718;"FFTMM;"
Description
Starts the continuous FIT.
Finds the sign& with the highest amplitude (usually the signal
at 0 Hz).
Finds the signal with the next highest amplitude (usually the
dominant modulation frequency).
Moves the signal to FFT midscreen.
FFI’MM is performed only if the spectrum analyzer is performing a FFI’ measurement.
Changing the FFI midscreen frequency of the spectrum analyzer also changes the FFI’ stop
frequency of the spectrum analyzer. Because the FFl’ stop frequency is limited by sweep time
of the spectrum analyzer, it may not be possible to change the FFI’ midscreen frequency to the
frequency of the FFI marker. If the FFTMM command does not move the signal to the FFT
midscreen frequency, you should check if the FFT stop frequency is limited by the sweep time
range or the sweep time increments for your spectrum analyzer. The FFI’ stop frequency is
related to the sweep time as follows:
FFT stop frequency =
400
(Sweep time x 2)
Programming Commands 5-169