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Selecting Test Features
Adding Frequency Offset to SONET Signal
Tributary Offset ±100 ppm
1 Choose the amount of tributary offset required.
You can set the Offset in the range -100 ppm to +100 ppm in 1 ppm
steps using and .
The amount of applied Frequency Offset can be varied while
measurements are taking place.
Tributary offset affects the stuff rate but does not cause pointer
movements and can be used to test mapping jitter. If the combined
value of SONET line rate offset and tributary offset chosen is sufficient
to cause the maximum stuff rate to be exceeded the payload is offset to
prevent bit errors occurring and the maximum stuff rate is
maintained.
DECREASE DIGIT INCREASE DIGIT