See :configure[1..n]:analysis, Rbscatter, Configure[1..n]:analysis:rbscatter – EXFO FTB-7000 OTDR Series for FTB-500 User Manual
Page 401

SCPI Command Reference
OTDR
387
Product-Specific Commands—Description
:CONFigure[1..n]:ANAlysis:RBScatter
Description
This command sets the Rayleigh backscatter that
will be used for the next acquisition.
*RST reverts this setting to default value.
Syntax
:CONFigure[1..n]:ANAlysis:RBScatter<wsp><R
BS>|MAXimum|MINimum|DEFault
Parameter(s)
RBS:
The program data syntax for <RBS> is defined
as a <numeric_value> element. The <RBS>
special forms MINimum, MAXimum and DEFault
are accepted on input.
MINimum allows to set the instrument to the
smallest supported value.
MAXimum allows to set the instrument to the
greatest supported value.
DEFault allows the instrument to select a value
for the <RBS> parameter.
Sets the Rayleigh backscatter.
Example(s)
CONF:ANA:RBS? Ex.: Returns –79.5
CONF:ANA:RBS –80
CONF:ANA:RBS? Returns –80