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CHAPTER 6: Cable Test Descriptions
NOTE
The cable should not be connected to an active network during the Noise
test, because the test will record network traffic as noise impulses.
6.6.2 V
IEWING
N
OISE
R
ESULTS
The display provides a continuously updated, real-time report illustrated by
the following figure:
NOTE
When testing a 10BASE-T cable per the IEEE 802.3 specification, the
maximum allowable impulse-noise rate is 0.2 impulses per second with a
260-mV noise threshold.
6.7 Pair Reversal Test
The Pair Reversal Test provides a means to verify the NEXT measurement
consistency of the SCAN-LAN VI as recommended by the draft TIA TSB-67
Link Testing Standard. In the Pair Reversal Test, the NEXT of a link is first
measured when transmitting on one pair and receiving on another. Then
the test is performed again with the transmit and receive pairs reversed. The
results should agree within the magnitude of the SCAN-LAN VI’s NEXT
measurement-accuracy specification. The test is performed automatically
on all pair combinations.
R
UNNING
PAIR REVERSAL
1. Connect one end of the cable under test to the SCAN-LAN VI and the
other end to the remote unit. Set the remote unit’s dial to REMOTE.
2. Set the dial to EXTENDED FUNCTIONS.
F1
F2
F3
F4
Summary of Contents for SCAN-LAN VI
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