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HP OMNIBER 718 HP 37718A User Manual

Page 100

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Making Measurements

Measuring Jitter Tolerance

2

If you are performing jitter tolerance on the SONET signal, set up the
SONET transmit and receive interfaces. See “Setting SONET
Transmit Interface” page 4 and “Setting SONET Receive Interface”
page 17.

3

If SONET is chosen as the interface, choose the SONET MASK.
TYPE A masks as per ITU-T G.958 have good jitter tolerance and the
mask corner points are modified to compensate.
TYPE B masks as per ITU-T G.958 have poorer jitter tolerance but a
narrower jitter transfer function and the mask corner points are
modified to compensate.

4

Choose the required test PATTERN.

5

Choose the NUMBER OF POINTS at which jitter is transmitted (3 to

55)

6

Choose the DWELL TIME - the time jitter is generated at each jitter
frequency point (1 to 99.9 seconds).

7

Choose the DELAY TIME - the time delay between the jitter
frequency/amplitude being applied and the error measurement being
made. This allows the network equipment to settle as jitter frequency
is changed. (0 to 99.9 seconds).

8

Choose the ERROR THRESHOLD.
If ANY ERRORS is chosen, any BIP or BIT error will result in a FAIL.
If BIT ERRORS is chosen, choose a value between 1 and 1,000,000 to
determine the bit error threshold for the jitter tolerance PASS/FAIL
decision.
BER>= shows the bit error ratio calculated from the bit error
threshold choice and the dwell time choice.

9

Press

to start the jitter auto tolerance measurement.

The measurements progress can be monitored on the
display. At the end of the test the results can be viewed on the

or

displays. The

display is cleared

when

is pressed but the results remain on the

display until the next jitter tolerance measurement is made.

RUN/STOP

TRANSMIT

TRANSMIT

RESULTS

TRANSMIT

TRANSMIT

RESULTS