Tektronix TekRanger 2 TFS3031, Руководство по обслуживанию

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Performance Check – TekRanger (serial nos. below B052000)
TFS3031 TekRanger/TekRanger 2 Service Manual
3–11
7. Connect the FCPC connector to the OTDR. Do not use an interface or
jumper cable. Measure the 1310-nm reflectance (return loss) at the event
located at 3.9 km. (See figure 3–4.)
Return loss: 40 dB dB) at 1310 and 1550 nm.
Insertion loss: <0.5 dB
3.9 km
4.4
km
Figure 3–4: Desired OTDR Signature
8. If the reflectance as read on the OTDR is under –43 dB or above –35 dB, the
previous steps have not been followed correctly, or there is a defective
component. Confirm that the fibers have been used and spliced properly in
each step above, correct any errors, and repeat the measurement.
9. If the reflectance is under 40 dB, re-splice (tune) the splice made in step 5
until 40 db ( 1 dB) is obtained. Remove the splice from the fusion splicer
and protect the splice with an appropriate splice-protection device.
10. Identify the 1550 fibers on each of the multiplexers. The length of these
fibers must match ( 2 inches) the 1310 fibers (step 5). Prepare and splice
these fibers together (splice #6). Do not remove them from the splicer at this
time.
11. Switch the OTDR to the 1550-nm wavelength and measure the 1550-nm
reflectance (return loss) from the event at 3.9 km.
12. If the reflectance is under 40 dB, re-splice (tune) the splice made in step 10
until 40 dB ( 1 dB) is obtained. Remove the splice from the fusion splicer
and protect the splice with an appropriate splice-protection device.
13. Mount the fiber fixture in a suitable enclosure. Leave the FCPC connector
and cable protruding from the fixture (do not use a bulkhead feedthrough).
The fixture must be connected to the instrument to be tested without using
an interface cable.