Keysight Technologies N4374B, User Manual

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Maintenance
108
Keysight
N4374B Lightwave Component Analyzer, User’s Guide
Cleaning interfaces is difficult as the core diameter of a single-
mode fiber is only about 9
m
m. This generally means you cannot
see streaks or scratches on the surface. To be certain of the
degree of pollution on the surface of your interface and to check
whether it has been removed after cleaning, you need a
microscope.
To assess the projection of the emitted light beam you can use
an infrared sensor card. Hold the card approximately 5 cm from
the interface. The invisible emitted light is projected onto the
card and becomes visible as a small circular spot.
Preferred procedure
Use the following procedure on most
occasions.
1 Clean the interface by rubbing a new, dry cotton swab over
the surface using a small circular movement.
2 Blow away any remaining lint with compressed air.
Procedure for stubborn dirt Use this procedure when there is
greasy dirt on the interface.
1 Moisten a new cotton swab with isopropyl alcohol.
2 Clean the interface by rubbing the cotton swab over the
surface using a small circular movement.
3 Take a new, dry soft tissue and remove the alcohol, dissolved
sediment and dust, by rubbing gently over the surface using a
small circular movement.
4 Blow away any remaining lint with compressed air.
How to clean instruments with a recessed lens interface
For instruments with a deeply recessed lens interface (for
example the
Keysight
Technologies 81633A and 81634A Power
Sensors) do NOT follow this procedure. Alcohol and compressed
air could damage your lens even further.
Keep your dust and shutter caps on when your instrument is not
in use. This should prevent it from getting too dirty.
If you must clean such instruments, please refer the instrument
to the skilled personnel of the
Keysight
service team.
Never look into an optical output, because this can seriously
damage your eyesight.
WARN IN G