Telecommunications Techniques Corporation interceptor 147, Справочное руководство, Страница: 63 / 280

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INTERCEPTOR 147 2 Mbit/s and Data Analyzer
Setup Categories
lost, the test instrument does not re-initiate the auto-
sync process. Instead, the test instrument indicates
loss of pattern sync and attempts to reacquire pattern
sync using the pattern that was detected when auto-
sync was initally achieved. This procedure ensures
that the test instrument properly reports loss of sync,
rather than simply revert to the default.
MARK
All 1’s pattern (1111, etc.).
SPACE
All 0’s pattern (0000, etc.).
1:1
Alternating 1’s and 0’s (10101010, etc.).
1:3
1 followed by three 0’s (10001000, etc.)
1:4
1 followed by four 0’s (1000010000, etc.).
2^6-1
63-bit pseudorandom pattern with a maximum of 5
sequential zeros and 6 sequential ones (as described
in CCITT Recommendation Q5 and Q6).
2^9-1
511-bit pseudorandom pattern with a maximum of 8
sequential zeros and 9 sequential ones (as described
in CCITT Recommendation V.52).
2^11-1
2,047-bit pseudorandom pattern with a maximum of
10 sequential zeros and 11 sequential ones (as
described in CCITT Recommendation O.152).
2^15-1
32,767-bit pseudorandom pattern with a maximum of
14 sequential zeros and 15 sequential ones (as
described in CCITT Recommendation O.151).