Stanford Research Systems SR865A, Operation Manual

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126 Programming Chapter 4
SR865A DSP Lock-in Amplifier
FAUT
The FAUT command performs an Auto Scale on the FFT display. This command is the
same as pressing the button in the FFT vertical scale palette.
FFTMAXSPAN?
The FFTMAXSPAN? query returns the maximum allowed FFT span (Hz/div) for the
current FFT source and lock-in configuration (time constant and reference frequency).
Example
FFTMAXSPAN? Returns the maximum allowed FFT span in Hz/div
FFTSPAN(?) { x }
The FFTSPAN x command sets the FFT span to x Hz/div. The value of x may not exceed
the maximum allowed span (as returned by FFTMAXSPAN? ). The FFT span will be set to
the nearest allowed span (max span divided by powers of 2).
Example
FFTSPAN 305 Set the FFT span to 305.2 Hz/div
FFTSPAN?
Returns the FFT span in Hz/div
FFTA(?) { AVG1 | AVG3 | AVG10 | AVG30 | AVG100 | i }
The FFTA i command sets the FFT averaging to 1 (i=0), 3 (i=1), 10 (i=2), 30 (i=3) or 100
(i=4).
Example
FFTA AVG3 Set the FFT averaging to 3
FFTA 1
FFTA?
Returns the FFT averaging i
FFTL(?) { OFF | ON | i }
The
FFTL i
command pauses (i=0) or resumes (i=1) the FFT graphing.
Example
FFTL OFF Pause the FFT graph
FFTL 0
FFTL?
Returns the FFT graphing i
FCRW(?) { LIne | NARrow | WIde | i }
The FCRW i command sets the cursor width to line (i=0), narrow (i=1) or wide (i=2).
Example
FCRW NAR Set the cursor to narrow
FCRW 1
FCRW?
Returns the cursor width i