HP (Hewlett-Packard) 86140A TV Cables User Manual


 
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
book.book Page 19 Monday, January 31, 2000 10:34 AM