Mike.
Please correct me, but from what I read in your initial log, the two T1 CSU/DSU's have achieved frame synch over the new T1 link. However what I don't understand is how the ciruit is being used based on the following quote;
"The CSUs/DSUs at both ends of the new path "lock right up" to each other fine (solid green on the link, TD, and RD of both CSU/DSUs). However, once the old circuit is applied to the new path via the EIA-530 connections on each of the CSU/DSUs, we're receiving an amber alarm on the xmit of one CSU/DSU, and an amber alarm on the receive of the other CSU/DSU. The remaining LEDs (with exception to the "ALM" LED) are still solid green."
Is the reference to the "OLD CIRCUIT" actually the terminal (CPE) equipment that is being thrown onto the new T1 circuit path at each customer location?
Are the CSU/DSU's CPE interfaces strictly DB-25 EIA-520 interfaces used for data?
What type of alarm is being reported by the CSU/DSU's? Is there a designation label to the alarm LED's mentioned?
How is the circuit being used on an end to end basis?
As for a DDS interface, as we know; DDS uses the same physical eight pin modular jack/plug as a T1 interface. However the wiring and pin outs differ substantially.
DDS uses a RJ-48S interface with the CSR transmit on pins 1&2 to Telco, CSR receive on pins 7&8.
A T1 will use a RJ-48C (Or X) interface with CSR transmit to Telco on pins 4&5, and CSR receive on pins 1&2.
If there was a screw up with DDS, the pins will not line up, plus the CSU/DSU's will never synch and report a LOS RED alarm (Loss of signal).
But as a sanity check, the mounting hardware that is used at the custmer location to house either T1 Smartjacks, HDSL HTU-R (Remote's), or 2Wire IDSL-DDS OCU-R NCTE field housing units have a selectable switch to choose either a RJ-48C/S interface. Depending on the type of circuit delivered, and remote unit installed. Most, if not all Verizon stand alone NCTE field housing units have this feature. Other Telco companies may also use the same NCTe housing supplier these days, typically Westell, or one of the companies that it merged with.
If the Telco tech, assuming it's Vz, that instaled your circuit set the NCTE mounting to the DDS option, RJ-48S, your circuit would not work.
A T1 optioned for B8ZS will pass any type of DS0 channel (56 or 64Kbs), since the B8ZS option to AMI T1 lines is designed to allow unrestricted zeros to pass over a T1.
Regarding SF/ESF. If the circuit is a dedicated link between to points, and the Telco does not perform any DS0 multiplexing, such as a channel bank or T1 MUX, then the T1 frame format can be changed, as long as each end is optioned with the same T1 frame format. As for AMI/B8ZS, changing the line code of the CPE requires the Telco to change the line code setting on their MUX/HDSL equipment to match the CPE.
Since the CSU/DSU can be accessed by a Hyperterm, VT-100 session, take a look at the alarm menu screen to try and determine what type of alarm(s) is being reported.
Regards & a belated Merry Christmas.
Bill
