2
61291006L2-5B
Section 61291006L2, Issue 2
2. OPTIONS
Select the appropriate OPTIONS and RATE using
SW1 and faceplate switches as illustrated in Figure 3
and Figure 4.
CAUTION
Select only one option rate. Rate is selected on
faceplate switch SW2 by pushing one or two
switches to the right toward the inscribed
rates. If either SW56 or 64 is selected, the
secondary channel (SC) switch may not be
selected.
A/B Signaling
When A/B Signaling (SW1-1) is OFF, the unit derives
signaling from the incoming data stream. When A/B
signaling is ON, the unit determines the state of the A
and B signaling bits using signals present on the
backplane of the channel bank. This method assumes
that proper signaling has been maintained throughout
network tandems and cross connect systems.
NOTE
A/B option is only applicable when SW56 is
selected; otherwise the option is a “don’t care.”
Quality Monitor
When Quality Monitor (SW1-2) is ON, the unit
monitors the incoming two-wire loop and four-wire
customer interface data for errors. If excessive errors
are detected, the unit blocks customer data
transmission and sends Abnormal Station Code to the
network. Customer data transmission is automatically
restored when the trouble condition is cleared. The
Quality Monitor feature is recommended for use on
multipoint circuits.
NOTE
Do not use in SLC-96 Mode II unless unit is
provisioned through Digital System-6.
NOTE
The TROCU DP must be used with an
appropriate TRDDS-R unit.
Features
In addition to operation over extended ranges the
TROCU DP incorporates or supports the following:
•
Two-wire deployment.
•
Repeaterless operation.
•
Bridged tap tolerant
•
Span power for remote TRDDS-R termination
unit.
•
Utilization in all D4 channel bank and SLC-96
Mode I or III remote terminal applications.
•
NEAR and FAR logic level bantam test access.
•
Loop Quality Monitor and A/B signaling
options.
•
Embedded Digital System 6 capabilities for
remote provisioning, configuration, and
performance monitoring.
Line Code
The ADTRAN TRDDS incorporates Simple Coded-
Pulse Amplitude Modulation (SC PAM), a line code
that reduces the bandwidth needed to transport signals
over copper loops. The Power Spectrum Density
(PSD) of SC PAM complies with Basic Rate Interface
(BRI) PSD mask as specified in ANSI T1.601 and is
below allowable 2B1Q PSD levels. SC PAM
increases the deployment ranges and allowable
bridged tap lengths when compared to AMI and
2B1Q. Additionally, SC PAM has an improved
spectral compatibility when compared to AMI and
2B1Q.
Sealing Current
The TROCU DP provides a constant 10 mA sealing
current to the TRDDS-R. With 10 mA sealing current
and span power of -130 Vdc, ADTRAN’s TRDDS
system is in the A3 Class as specified in Bellcore
TR-NWT-001089, Standard for Electrical Safety for
Network Telecommunications Equipment.
Figure 3. Option
Switch
SW1
A/B Signaling
Quality Monitor
1
ON
2
OFF
OFF
Figure 4. Rate
Selection
ON
78
56
4
23
1
SW56
2.4
4.8
9.6
19.2
56
64
SC
