HP 83447A, Руководство пользователя и сервисное руководство

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Installation and Preparation for Use
Cleaning Connections for Accurate Measurements
Dust Caps Provided with Lightwave Instruments
Item HP Part Number
Laser shutter cap 08145-64521
FC/PC dust cap 08154-44102
Biconic dust cap 08154-44105
DIN dust cap 5040-9364
HMS10/HP dust cap 5040-9361
ST dust cap 5040-9366
Inspecting Fiber-Optic
Cables
Consistent measurements with your lightwave equipment are a good
indication that you have good connections . However , you may wish to know
the insertion loss and/or return loss of your lightwave cables or accessories . If
you test your cables and accessories for insertion loss and return loss upon
receipt, and retain the measured data for comparison, you will be able to tell
in the future if any degradation has occurred.
Connector (or insertion) loss is one important performance characteristic of a
lightwave connector . Typical values are less than 1 dB of loss , and sometimes
as little as 0.1 dB of loss with high performance connectors . Return loss
is another important factor . It is a measure of reection: the less reection
the better (the larger the return loss , the smaller the reection). The best
physically contacting connectors have return losses better than 50 dB ,
although 30 to 40 dB is more common.
Y ou can visually inspect your cables
Although it is not necessary , visual inspection of ber ends can be helpful. Contamination or
imperfections on the cable end face can be detected as well as cracks or chips in the ber itself . Use
a microscope (100X to 200X magnication) to inspect the entire end face for contamination, raised
metal, or dents in the metal as well as an y other imperfections. Inspect the ber for cracks and chips.
Visible imperfections not touching the ber core ma y not aect performance (unless the imperfections
keep the bers from contacting).
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