4-19
Remote Operation
Example Programs
Example 3. Bandwidth
Description
The 20 dB marker BW function is used to determine the bandwidth of the sig-
nal. The program assumes a narrowband signal as an input.
Program
PRINT
PRINT “20 dB Bandwidth example”
OUTPUT 723;”disp:wind:text:data ‘Signal Bandwidth Measurement’”
!
PRINT
PRINT “Presetting the instrument”
OUTPUT 723;”*rst” ! Preset the instrument
!
PRINT
OUTPUT 723;”disp:wind:trac:all:scal:auto” ! Automeasure
PRINT “Performing Automeasure”
!
PRINT
OUTPUT 723;”cal:alig:mark1” ! Perform an autoalign
PRINT “Performing Autoalign”
!
! Next line is the operation complete query used so that the text is not printed
! until after the Autoalign is complete
OUTPUT 723;”*opc?”
ENTER 723;Dum
PRINT “ ...measurement begins”
PRINT
!
OUTPUT 723;”sens:wav:span 10 nm” ! Set span
!
OUTPUT 723;”init:imm” ! Take a sweep
OUTPUT 723;”calc1:mark1:max” ! Marker to peak
OUTPUT 723;”calc1:mark1:scen” ! Marker to center
!
OUTPUT 723;”calc1:mark1:x?” ! Read marker wavelength
ENTER 723;Markwl
OUTPUT 723;”calc1:mark1:y?” ! Read marker amplitude
ENTER 723;Markamp
! Convert to standard measurement units (nm)
Markwl=Markwl*1.E+9
PRINT “Marker wavelength”;Markwl;”nm”
PRINT “Marker amplitude”;Markamp;”dBm”
PRINT
!
OUTPUT 723;”sens:bwid:res 0.1 nm” ! Set resolution bandwidth to min
OUTPUT 723;”sens:wav:span 2 nm” ! Set span to higher resolution
OUTPUT 723;”init:imm” ! Take a single sweep
!
OUTPUT 723;”calc1:mark1:max” ! Marker to peak for reference point
!
OUTPUT 723;”calc1:mark1:func:bwid:ndb -20.0 db” ! Selects db down where bw is calculated
OUTPUT 723;”calc1:mark1:func:bwid:int on” ! Enable bw marker interpolation
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