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SCAN-LAN VI
6.5 ACR
Attenuation-to-Crosstalk Ratio (ACR) is the difference between crosstalk
and attenuation, measured in dB, at a given frequency. ACR is computed
based on the measured values of attenuation and NEXT.
A positive ACR is necessary to assure that a signal at the receiving end of a
channel is stronger than the crosstalk interference imposed from adjacent
wire pairs. ACR is therefore an indication of the expected reliability of data
transmissions.
ACR is automatically computed during Autotest and Quick Check when
testing twisted-pair cable. It can also be run individually as an Extended
Function test.
6.5.1 R
UNNING
ACR
1. Set the dial to EXTENDED FUNCTIONS.
2. Press the arrow keys to highlight ACR.
3. Press ENTER. The test begins scanning immediately. (Press the arrow
keys to select another cable test standard.)
6.5.2 V
IEWING
ACR R
ESULTS
For each pair combination the ACR is displayed along with the frequency.
The attenuation value used is from the receive pair (for example, pair 3,6
of 12/36).
F1
F2
F3
F4
Summary of Contents for SCAN-LAN VI
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