TTC T-BERD 107A, Reference Manual

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SECTION 3
3-9
INSTRUMENT
DESCRIPTION
ERR INS and B8ZS switches are disabled in this
mode. To obtain logic error test results, the
T-BERD 107A test pattern must match the
received test pattern.
In the T1 LLB mode, the LOOP CODES, LOOP
UP, and LOOP DOWN switches are disabled,
and the RCVD switch automatically defaults to
recovered timing (LED illuminated).
AUTO LLB — Automatically responds to a
received loop-up code. AUTO LLB is not se-
lectable by the
MODE switch. The AUX
AUTORESP function must be set to AUTO
RESPONSE for the T-BERD 107A to respond
to a received loop code. The T-BERD 107A will
only respond to a loop code that matches the
loop code type selected in the AUX CSU LOOP
function, AUX NIU LOOP function, or AUX
PROGLOOP function and by the
LOOP CODES
switch. In AUTO LLB mode, the T-BERD
107A functions the same as the T1 LLB operat-
ing mode.
AUTO LLB mode is enabled after receiving
either five seconds of an in-band loop-up code or
250 ms of an ESF out-of-band loop-up code. If
the T-BERD 107A is set to T1 LLB or T1 TLB
mode, it will not respond to the received loop
codes. The AUTO LLB mode is exited by
receiving an in-band or an ESF out-of-band
loop-down code, or by powering down the in-
strument. When the loopback is disabled, the
instrument returns to the previously selected
operating mode.