Tellabs 6122 Manual

Ttellabs
technical manual
76-826122A
rev B
practice section 816122/826122A
©Tellabs, Inc., 2 August 1983
all rights reserved, printed in USA
p/o
6122 and 6122A 2Wire E&M SF Signaling Sets
page 1
page
3
page 9
page
17
page 23
page 17
page 22
contents
section 1
general description
section 2 application
section 3 installation
section 4 circuit description
section 5 block diagram
section 6 specifications
section 7 testing and troubleshooting
1. general description
1.01 The 6122 2Wire E&M SF Signaling Set mod-
ule with Gain and the 6122A 2Wire E&M SF Signal-
ing Set module with Gain and Loopback (figure 1)
each provide signaling and transmission interface
between a 4wire facility that uses single-frequency
(SF) signaling and a 2wire trunk (typically, a PBX
trunk) or a 2wire line that uses E&M signaling. Both
modules provide active level control in the transmit
and receive paths, receive-path amplitude equal-
ization, and full-duplex signaling conversion be-
tween the SF signaling on the 4wire facility and the
E&M signaling on the 2wire trunk or line. Conven-
tional 2600Hz SF tone is supplied by an integral
oscillator. The 6122 and 6122A diHer from ordinary
2wire E&M SF signaling sets in that they each con-
tain an integral line amplifier to accommodate a
variety of facility interface levels. Unlike the 6122,
the 6122A contains integral loopback circuitry to
facilitate local or remote testing of the module and
the facility. As members of Tellabs' 262U Universal
Network Terminating System of modules and en-
closures, the 6122 and 6122A each fulfill Regis-
tered Facility Interface Codes TCll E, TCll M, TC12E,
TC12M, TLllE, TLllM, TL12E, and TL12M for
network-terminating applications where the serv-
ing telephone company uses SF signaling.
1.02 In the event that this practice section is
reissued, the reason for reissue will be stated in
this paragraph.
1.03 Features and options of the 6122 and
6122A include the following: full prescription align-
ment capability; balanced, switchable 1200, 600, or
150-ohm terminating impedances on the 4wire
(facility) side; balanced, switchable 900 or 600-ohm
terminating impedance (in series with 2.15/LF) on
the 2wire (terminal) side; facility-side amplifiers and
terminal-side attenuators for interfacing at a
variety of levels; active slope-type receive equaliza-
tion; an integral compromise balance network;
switch-selectable network build-out capacitance;
switch-selectable A-side or B-side E&M signaling;
switch-selectable Type I, II, or III E&M interface;
minimum-break transmit and receive pulse correc-
tion; and an integral sealing-current source. The
6122A alone contains the aforementioned loop-
page 1
figure
1. 6122
and 6122A 2Wire SF
Signaling Set modutes with Gain
back circuitry with both local (manual) and remote
(two-tone) loopback-state control. In place of this
loopback circuitry, the 6122 makes provision for
use of an optional precision balance network sub-
assembly. Except for these diHerences, the two
modules are identical.
1.04 Prescription-set transmit and receive ampli-
fiers on the 4wire side of the 6122 and 6122A
allow each module to interface the SF signaling
facility directly, I.e., without a separate facility-side
line amplifier. These integral amplifiers, in conjunc-
tion with prescription-set transmit and receive
attenuators on the 2wire side (but located in the
4wire paths), provide for full coordination between
facility-side and terminal-side levels. Both facility-
side amplifiers on each module provide from 0 to
24dB of gain in switch-selectable 0.1 dB incre-
ments, and both terminal-side attenauators provide
from 0 to 24dB of loss in switch-selectable O.ldB
increments. In the receive channel, 4wire input
TLP's from -17 to +7 can be accommodated and
2wire output TLP's from +7 to -17 can be derived.
In the transmit channel, 2wire input TLP's from -16
to +8 can be accommodated and 4wire output
TLP's from +8 to -16 can be derived. Overload
points at each module's ports are as follows: 4wire
receive port, +5dBmO; 4wire transmit port, +5dBmO;
2wire-port input, +5dBmO; 2wire-port output,
+8dBm.
1.05 An active slope equalizer for nonloaded
cable in the receive channel of the 6122 and
6122A permits from 0 to 7.5dB of equalized gain to