Administrator's Guide

Screen reference
555-233-5061292 Issue 5 October 2002
The following table explains the differences between types of terminating test
lines:
The far-end switch containing the TTL may be any of the following:
■ System 85 R2 switch, equipped with the Maintenance/Test Board
(TN771B)
■ System 75 R1V2 and beyond, all of which contain the circuitry required to
perform the TTL function
■ System 85 R2 switch, equipped with the Analog/Digital Facility Test
Circuit (ADFTC, SN261)
■ DIMENSION FP8, equipped with the Analog Facility Test Circuit (AFTC,
ZLC-12)
■ Central Office switches, equipped with various TTL equipment that
provide 100, 102, or 105 test line capabilities (56A)
Other vendors’ switches may be supported if compatible test lines are provided by
these switches.
low-lts
low-level tone source
100
100 type
102
102 type
Type TTL Description Example
105-w-rl Full range of 18
measurements or some
defaults for return loss used
(56A)
TN771B, ZLC12 and
SN261B circuit packs
and new 56A
mini-responder
105-wo-rl Cannot return default values
for far-end return loss
Older 56A
mini-responder
high-level-tone Sends a fixed sequence of
tones at 0 dBm
ZLC12 and SN261B
circuit packs
low-level-tone Sends a fixed sequence of
tones at -16dBm
SN261B circuit pack
100 Up to 5 measurements that
sends a 1004 Hz tone then a
quiet termination
102 One measurement that
sends a 1004 Hz tone
Valid entries Usage