TTC T-BERD 107A, Reference Manual

Page: 212 / 261

SECTION 7
SPECIFICATIONS
7-9
Pattern Loss: QRSS — 250 errors de-
tected in 1000 or fewer bits.
Fixed pattern — 100 errors
in 1000 or fewer bits.
Ones Density: QRSS — LED illumina-
tion is suppressed.
Other patterns — received
data contains less than n
ones in 8(n+1) bits, where
n = 1 to 23.
Excess Zeros: AMI - 16 or more consecu-
tive zeros.
B8ZS - 8 or more consecu-
tive zeros.
Yellow Alarm: D1D - Bit 2 is a 0 for 255
consecutive channels.
D4 - Bit 2 is a 0 for 255
consecutive channels.
ESF - 256 bits
±
16 bits of a
repetitive (1111 1111 0000
0000) pattern received in
the 4 kb/s datalink.
SLC - Bit 2 is a 0 for 255
consecutive channels.
AIS (Alarm Indication
Signal):
Unframed T1 signal has
2048 consecutive ones.