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

FFTAUTO Marker to Auto FFT
“Measuring Amplitude Modulation with the Fast Fourier Transform Function” in Chapter 4 of
the HP 8590 E-Series and LSeries Spectrum An&zers User’s Guide. You can use the results
of the FFTCLIP command to determine if the FFT data is valid.
Restrictions
Executing FFTAUTO turns off the following functions: windows display mode (WINON), N dB
point measurement (NDBPNT), gate utility functions (GDRVUTIL), TO1 measurement (TOI),
marker table (MKTBL), peak table (PKTBL), percent AM (PCTAM), peak zoom (PKZOOM),
power menu measurements (ACP, ACPE, CHP, and OBW), and Analog+ display mode
(ANLGPLUS).
FFTAUTO uses the following when performing an FFT:
� The flat top filter window. (See “FFT” for more information about the flat top filter window.)
w Trace B and trace C. If you want to save the trace data that is in trace B or trace C, you
should save the trace data before executing FFTAUTO, FFTCONTS, or FFTSNGLS. (See
“SAVET” for more information about saving trace data.)
� The FFTMKR command to turn on the FFT markers (you can use the MKA or MKF to
determine the amplitude or frequency of the marker).
Programming Commands 5-165