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T1.105/gr-253 pointer sequences explained – HP OMNIBER 718 HP 37718A User Manual

Page 65

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Selecting Test Features

Adding Pointer Adjustments

OFFSET - You can frequency offset the line rate or the SPE/VT rate,
relative to each other, thus producing pointer movements. If you offset
the SPE pointer, an 87:3 sequence of pointer movements is generated.
The available configurations are listed in the following table.
If you are currently adding Frequency Offset to the SONET interface
or payload, pointer OFFSET is not available.

T1.105/GR-253 - Provides pointer movements according to T1.105 and
GR-253:

4

Choose the T1.105/GR-253 ADJUSTMENT TYPE.

5

Choose the POLARITY, INTERVAL and PATTERN (where applicable)
for the selected sequence.

6

Choose POINTER SEQUENCES

to generate the selected

G.783 sequence and

to stop the pointer sequences.

T1.105/GR-253 Pointer Sequences Explained

In addition to the BURST, NEW POINTER and OFFSET pointer
movements described, the HP 37718A can also generate pointer
sequences (pointer movements) according to T1.105.03 and GR-253.

Before running a pointer sequence you can elect to run an initialization
sequence, followed by a cool down period, and then run the chosen
sequence. This is selected using the START INIT softkey shown in the
display on the previous page. Initialized pointer sequences are made up
of three periods: the Initialization Period, the Cool Down Period, and the
Sequence (Measurement) Period, an example is given in the following
figure:

Pointer Type

Line Rate

SPE Rate

VT Rate

SPE

Constant

Offset

Tracks AU Payload

SPE

Offset

Constant

Constant

VT

Constant

Constant

Offset

VT

Offset

Tracks Line Rate

Constant

START INIT

STOP INIT