Tektronix TekRanger 2 TFS3031, Service Manual

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Performance Check – TekRanger 2 (serial nos. B052000 and above)
TFS3031 TekRanger/TekRanger 2 Service Manual
4–7
Singlemode Dead-Zone Test Fixture
The dead-zone test fixture is used to verify event and attenuation dead zone. It
consists of two 1.1-km (
±
100 m) spools of Corning SMF28 singlemode fiber
including:
H
95/5 singlemode coupler
H
1310nm/1550 nm WDM
H
FC/PC connector
PORT A
Termination
FC/PC Connector < .1dB Splice
1.1km
1.1km
WDM
1310nm
1550nm
Quality
Cleave
Quality
Cleave
Bend Atten
Bend Atten
Length of this leg
of fixture is approx. 3m
Bend losses are adjusted when
built to give a –40dB reflection
at each wavelength
Figure 4–2: Singlemode Dead-Zone Test Fixture
Assemble and characterize this fixture as follows:
1. Fusion splice an FC/PC connector to one end of the first 1.1-km spool of
Corning SMF28 singlemode fiber.
2. Fusion splice the other end of the first 1.1-km spool to the input of the 95/5
coupler.
3. Fusion splice one end of the second 1.1-km spool of fiber to the 95% port of
the 95/5 coupler.
4. Terminate the other end of the second 1.1-km spool of fiber by wrapping and
securing the end of the fiber eight times around a two-inch section of a
0.3-inch diameter mandrel.
5. Fusion splice the 5% leg of the 95/5 coupler to the input of the WDM.
6. Cut the 1310-nm and 1550-nm legs of the WDM to one meter.