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CHAPTER 6: Cable Test Descriptions
2. Press PAIR (F1) to display an Attenuation graph for a different pair.
3. Press the arrow keys to move the cursor to another point on the graph.
4. Press SEND (F2) to send the results to the remote unit.
5. Press PRINT (F4) to send a comma-separated variable (CSV) listing
of the results to the serial port. This provides a complete listing of all
Attenuation measurements for all pairs.
6. Press SUMMARY (F3) or ESC to return to the summary screen.
6.4.4 M
ARGINAL
T
EST
R
ESULTS
A PASS* or FAIL* result (PASS or FAIL with an asterisk) indicates that a
measured NEXT or attenuation value is close enough to the Test Standard
that it is within the measurement uncertainty of the SCAN-LAN VI. As a
result, the PASS or FAIL judgment is uncertain, and therefore the SCAN-LAN
VI cannot determine with confidence whether the link conforms to the Test
Standard.
The following steps may be taken in order to resolve link tests with marginal
measured results:
1. Reduce the measurement uncertainty. If you are currently using a Level I-
rated Performance Module (PM), replace it with a Level II-rated PM and
retest. If the test result is still marginal, or if you are already using a Level
II-rated PM, go to the next step.
2. Recheck the link installation, focusing on connection points. Refer to
Chapter 8, Testing Twisted-Pair Cable
, for suggestions on causes for
excessive NEXT and attenuation. Correct the installation, if possible,
and retest.
F1
F2
F3
F4
Содержание SCAN-LAN VI
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