OptoTest OP940-SW Instruction Manual page 33

Front Panel Operation
Bidirectional Functionality – OP725
Overview
On single channel OP940s, the user has the option to control an OP725-2x2 to perform
bidirectional measurements through the front panel. When operating in this mode, most
mode screens will function largely the same as with the standard configuration, but
some additional functions will be added to allow the unit to measure bidirectionally and
appropriately store the reference values.
Enabling Bidirectional Mode
The mode can be toggled on or off by navigating to
the Settings screen and finding the option named
"External 2x2 Switch". Selecting "Enable" will
put the unit into bidirectional mode and "Disable"
puts the unit into standard mode. In order to
have these changes take effect, the unit must be
restarted after the settings are saved.
Operating the OP940 Bidirectionally (OP725)
When in bidirectional mode, most of mode screens (IL, RL, ILRL, Dual ILRL, Scan, IL
Ref, and RL Ref) have some added features. For example, each of these modes get a
function that sends a command to the OP725 to toggle between Bar State and
A B
B A
Crossed State. Using this function on each of the screens allows the user to switch
between the forward direction and the reverse direction. It also saves the reference
parameters for insertion loss and return loss in each direction and will use the appropriate
parameters when switching directions.
For example, after referencing insertion loss in the forward direction, the user would want
to select the function to switch directions and reference again in the other direction.
A B
B A
The same would be true for return loss referencing and while taking measurements for
the device under test.
When operated in Bidirectional Mode, Scan Mode's screens change to accommodate the
addition of a feature. All other functionality remains intact.
A B
B A
NOTE: When operating the OP725 | OP940 tandem in Bidirectional Mode, all
operations to control the OP725 must be done through the OP940 and not using
the front panel controls of the OP725.
Startup Mode
External 2x2
Temperature Units
32 of 49
OP940-SW
Global Settings