MBR5 User Manual
MBR5 Rev 007
19
Figure 7: Backreflection measurement area
Measuring BR (Excluding the Connector)
The method described in the “MEASURING BR (Including Connector)” section is
used to measure the backreflection if the DUT is a connector, or if the DUT is a
connectorized component and the total backreflection from the connector and
the DUT is desired.
It is sometimes desirable to know the backreflection of a connectorized DUT,
but excluding the connector. If the fiber type is single-‐mode, this is possible, but
a few extra steps must be taken for every measurement to reference out the
connector (i.e., the user must do a BR0 for every DUT).
Refer to the “MEASURING BR (Including Connector)” section and redo the BR0
measurements for each wavelength, but this time, when terminating between
the DUT’s connector and the DUT. Note that if a BR0 value has already been
stored, it is required to press the BR0 button first, to erase it and then press it
again to store the new value.
Create a termination point on the pigtail after the DUT. The meter now displays
the backreflection of the DUT only.
Termination
Point
for BR
TOTAL
Termination
Point
for BR
0
Measurement
Jumper
DUT
FC/APC
850
1310
1550
DETECTOR
CHANNEL
1
MENU
LOCAL
BR
BR
O
POWER
REF DARK
MBR5 Backreflection Meter
-58.0dB 1310
1
BACKREFLECTION
I
O
