User guide

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OMNIScanner User Guide
Delay is a measure of the time required for a pulse to travel from one end
of the circuit to the other. OMNIScanner measures the delay between when
the pulse was sent and when the reflection was received. Knowing the
speed that the pulse propagates down the cable (NVP), OMNIScanner
then calculates the length of the cable.
Skew is the difference between the delay on the longest and shortest
wirepairs.
The LENGTH/DELAY screen shows the test result
information for all pairs.
The Limit is displayed at the top of the screen.
The pairs are displayed in the first column followed
by small icons to indicate whether the pair is open
or shorted .
The measured Length and the Delay are displayed for each pair. The result
for the shortest pair is tagged with a PASS or FAIL indicator.
The length result can be displayed in meters or feet.
Delay is displayed in nS (nanoseconds).
The Skew value and the Skew limit are displayed right below the pairs.
Press ESC to exit the LENGTH/DELAY screen.
NEXT
The NEXT (Near End Crosstalk) function measures the electromagnetic
coupling that occurs between pairs at the near end. OMNI Scanner and
OMNI Remote allow NEXT to be measured at both ends of the link without
having to swap ends.
OMNI Remote functions as a terminator while OMNI Scanner transmits a
signal which is monitored on the receive pair. The received signal is
compared to the transmitted signal and the difference is reported as the
NEXT value in dB. When measuring the NEXT for the OMNIRemote end,
the roles of the two units are reversed. OMNI Scanner provides the termina-
tion; OMNI Remote transmits and receives the signal.