Fluke DTX-1800, Техническое справочное руководство

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Certifying Twisted Pair Cabling
Twisted Pair Autotest Results
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Figure 3-19. ACR-N Plot
amd11f.eps
A
The location of the ACR-N results. Press
J
to switch
between the tester and smart remote.
B
The overall ACR-N result. “PASS*/FAIL* Results” on page 3-12
describes results marked with an asterisk.
C
Horizontal and vertical magnification levels for the plot. To
change the magnification, press
K
Change To Zoom; then
use
BC
or
AD
to zoom horizontally or vertically.
D
Measured ACR-N for the cable pairs. Higher ACR-N means
better cabling performance.
E
The limit line (in red) for ACR-N. The higher the
measurements rise above the limit line, the better the cabling
performance. If the line is black, ACR-N is not evaluated at
those frequencies. See page 3-13. Press
L
to see plots of
individual pairs.
F
The cursor and its location on the frequency scale. When you
first view the plot, the cursor is placed at the worst margin.
Use
BC
to move the cursor (if the plot is in zoom mode,
press
K
Change To Cursor first).
G
The measured ACR-N and margin at the cursor’s position.
Margin is the difference between the measured value and
the limit. Margin is negative if the pair failed.
H
The horizontal scale is the frequency range in megahertz. The
vertical scale is the ACR-N range in decibels.
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