Microtest TSB-67 - 568A Annex E - Manual (Page 25)

Page 25
Attenuation Test Results
To display the ATTENUATION screen, press View (F1) from the AUTOTEST RESULTS screen,
then press the ¬ arrow key until the ATTENUATION screen is displayed.
At the upper left of the screen, the pair corresponding to the displayed result is shown. The
Attenuation, in decibels (dB), is shown centered and the frequency is shown to the right. The
PASS/FAIL bar across the screen compares the measured Attenuation value to the Attenuation
limit value. The Autotest name is displayed after
Spec: at the lower left of the screen.
Press Detail (F1) to display the frequency sweep range and the test results for all pairs.
Press Pair (F3) to toggle through the Attenuation results for each pair combination.
Press the
Ï
or
Ð
arrow key to display the previous or next test results screen.
Press the ESCAPE key to return to the AUTOTEST RESULTS screen.
Note: For diagnostic purposes, you can run Attenuation continuously by pressing the Measure
Cable Performance key and selecting Attenuation.
Attenuation Detail
To display this screen, press Detail (F1) from the ATTENUATION screen. This screen displays the
frequency sweep range and the worst case Attenuation for each pair.
Press Graph (F1) to enter graphing mode. Graph (F1) is available when Save Sweep Data: Attn
has been selected in the SAVE AUTOTEST screen or when viewing results immediately after
running the Autotest.
Press Pair (F3) to toggle through the available pair combinations.
Press the ESCAPE key to return to the Attenuation screen.
Attenuation Graph
To display this screen, press Detail (F1) from the ATTENUATION screen, then press Graph (F1).
This screen displays the Attenuation graph for the indicated pair combination.
Press Zoom (F1) to magnify the area of the graph around the cursor. The Zoom key can select 1x,
2x, 5x or 10x magnification.
Press Print (F2) to print the Attenuation graph.
Press the ESCAPE key to return to the Attenuation Detail screen.
Attenuation-to-Crosstalk Ratio (ACR)
Attenuation-to-Crosstalk Ratio (ACR) is an indication of how much larger the received signal is
compared to the noise (NEXT) on the same pair. ACR reports the difference between NEXT and
Attenuation on the cable. Both Attenuation and NEXT are measured and the ACR value is
computed at each measured Attenuation frequency. The worst case ACR is reported for each pair
combination.