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CHAPTER 6: Cable Test Descriptions
Press START (F1) to restart the test.
NOTE
Minimum ACR is not presently specified in most link test standards
(such as TIA TSB-67) or network standards (such as IEEE 802.3). ISO
11801 requires at least 4 dB of ACR at 100 MHz. Hub manufacturers
recommend a minimum of 5 dB for reliable data transmission.
6.5.3 L
INK
P
ERFORMANCE
A
NALYSIS
B
EYOND
100 MH
Z
—ACR
AND
H
EADROOM
Power Sum ACR measurements beyond 100 MHz are valuable for determining
adequate performance of enhanced Category 5 cabling. Current Category 5
standards require a minimum of 10 dB ACR at 100 MHz. Proposed Category 6
standards recommend an ACR value of a minimum 10 dB ACR at 200 MHz.
System 6 provides this measure of cable performance up to 250 MHz. The
frequency at which the cable had a measured 10 dB ACR value is clearly displayed
in the LINK PERFORMANCE screen. The following graph illustrates the ACR vs.
Frequency relationship:
F1
F2
F3
F4
Summary of Contents for SCAN-LAN VI
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