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RM3 SERIES BACKREFLECTION METER
USER’S MANUAL
Backreflection Calibration Adjustment
The RM meter has a
To perform a backreflection calibration adjustment:
1.Press the BR key to set the RM meter to Backreflection mode, which is displayed as BR on the meter.
2.Clean and connect the APC connector (green boot) of the calibrated jumper to the output port of the RM meter.
3.Press the λ key to select the wavelength at which the calibration check is to be performed. Choose either wavelength, as you will check both.
4.Clean the output connector of the calibrated jumper. The backreflection value is displayed.
The value displayed on the RM meter must match the reference value that appears in the inspection report and on the label of the calibrated jumper. If these values do not match, ensure that the FC/APC connector is properly connected to the RM meter, and clean all the connectors. If the values still do not match to within ±0.3 dB, adjust the value of User CAL. The CAL key is located on the rear panel of the RM meter.
To adjust the value of User CAL:
1.Use a screwdriver or an appropriately narrow object to press the CAL key on the back of the RM meter. The last User CAL value stored is displayed on the RM meter.
2.Press and hold the Store BR0 key to scroll to the required value in 0.1 dB increments.
3.Press the CAL key to store the User CAL value and return the RM meter to the backreflection measurement display.
Perform calibration adjustment for the second wavelength:
1. Repeat the calibration adjustment procedure for the second wavelength.
Power Calibration Adjustment
To perform a power calibration adjustment:
1.Press the Power key to set the RM meter to Power mode. In Power mode, the meter displays P at the beginning of the reading, and the value displayed is not followed by “rel”. An example is P =
2.Clean and connect the FC/APC connector (green boot) of the calibrated jumper to the output port of the meter.
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