JDS Uniphase BACKREFLECTION METER RM3750 User Manual - page 14
RM3 SERIES BACKREFLECTION METER
USER’S MANUAL
10112341 Rev 002
Page 13 of 39
Output Port
The output port of the RM meter is equipped with an ultra-low backreflection APC connector.
To prevent damage to the output port connector, a measurement jumper must be used for all
measurements, even for measuring a component with an APC connector.
Internal Light Sources
The RM meter can be equipped with two internal laser sources. These are thermoelectrically
cooled for added stability and are modulated at 10 kHz. Fast changes in ambient temperature
can cause a source to become unstable. If this occurs, the meter automatically switches to a
measuring mode in which P
in
and P
dark
are measured more frequently than every minute and
the message “Source Unstable” is displayed. The light source power is monitored, and the
meter returns to the standard measurement mode when the source has stabilized.
Hybrid Jumpers
The RM meter is supplied with a hybrid measurement jumper and a hybrid calibrated jumper.
The measurement jumper has an APC connector at the input end. The other end on the
standard measurement jumper is PC, but by changing measurement jumpers this end is user-
selected, to be compatible with the input connector of the DUT. The calibrated jumper has an
APC connector at the input end and a PC connector at the output end.
Use the measurement jumper for measurement purposes only; use the calibrated jumper for
calibration purposes only. The calibrated jumper has a label attached to it identifying it as the
calibrated jumper.
Coherence Length
Reflected light from multiple reflections can change the backreflection measured by the
RM meter. This variation typically shows up as noise or drift in the signal. The internal light
source is designed to have low coherence length (typically less than 10 cm). Thus,
interference effects are typically seen only between very closely spaced components such as
non-contacting connectors.
Electrical Requirements
The RM meter is supplied with a rechargeable battery. When fully charged, the battery
provides up to eight hours of operation at room temperature. For laboratory use, use the
RM meter with the power cord. The letter B is shown on the RM meter front panel display when
the battery power is low.
Key Features
•
Backreflection measurements to -75 dB for single mode model (-40 dB for multi mode
model)
•
Power measurements to -80 dBm for single mode model (-60 dBm for multi mode model)
•
Convenient foot pedal for data logging
•
MCTS
application
software
•
Built-in light sources at 850, 980, 1310, 1480, 1550, 1625, or 1650 nm
•
Compensation for extraneous backreflection for accurate backreflection measurements