Toshiba Strata DK14 Installation And Maintenance Manual page 217

If there are two RDTU PCBs installed, it is recommended not to install the Primary and
Secondary Reference RDTU PCBs in the same DK424 cabinet if possible (although both
Primary and Secondary Reference RDTU PCBs can be installed in the same cabinet). The
Secondary Reference RDTU should also be connected to a Telco or Long Distance Provider
T1 span (*42-2, Data = 2 for this RDTU).
If the equipment on the other end of the DK424 T1 lines should synchronize to the DK424
clock source, then blanks should be entered in Program *42. In this case, the DK424 clock
runs free and is considered the Master Synchronization provider. The DK424 can be assigned
as the Master (free run) clock provider if the far end equipment connected to the RDTU T1
span is a Customer Premise type equipment and it is not synchronized to some other T1
provider (i.e., PBX, Channel Bank, Key/Hybrid or other DK424). In this case (when the Telco
network is not connected), either the DK424 RDTU span or the far end equipment can be the
Master (synchronization clock provider).
Program *42-1, Primary Timing Reference Assignment: Assign the Primary Timing
Reference with this program.
Program *42-2, Secondary Timing (Backup) Reference Assignment: Assign the Secondary
(Backup) Timing Reference with this program.
To assign RDTUs for the Master Clock Provider, leave Programs *42-1 and *42-2 blank. Press
button/LED01 to enter blanks.
The Digital Network is connected to clocks with various degrees of precision called
Important!
stratum levels from Stratum 1 (highest level of accuracy) to Stratum 4 (lowest level)
as follows:
Stratum 1—Public Telephone Network clock located in Hillsboro, Missouri.
•
Stratum 2—Normally associated with #4 ESS Toll switches.
•
Stratum 3—Normally associated with #5 ESS Central offices.
•
Stratum 4—Normally associated with Digital PBXs.
•
If a DK424 RDTU is programmed as the Primary Synchronization Clock
•
reference, the clock provider connected to this RDTU should be a reliable clock
provider, such as a Telco or common carrier (Example—AT&T). All other T1 span
lines connected to RDTUs in the DK424 must be synchronized to the same clock
source as the AT&T span line. If a T1 span line is not synchronized with the
primary clock provider (AT&T, for this example), then DK424 lines assigned to
this T1 span line (RDTU) may experience "slip" problems.
9. The programs in Steps 1~8 are described for specific RDTU application programming. Also
refer to "System Programming for T1"
CO line applications.
Strata DK I&M 5/99
on Page 6-3. Run the programs as they apply to RDTU
DK424 T1
RDTU T1 Interface Unit
6-7