Excessive line to line crosstalk on NT8D09CAE5 Analog Line Card !!!

[lucris]

Please have someone answer the problem below?

Excessive line to line crosstalk on NT8D09CAE5 Analog Line Card

Undesirable effect: it is possible to record call(s) with an usual recording device (like a recorder or laptop application) connected to one IDLE port of the NT8D09CAE5 analog line card.

Testing scenario;
1.- Communication Server 1000 PBX (any H/W or S/W version).
2.- two analog line cards: one NT8D09AL (old H/W)-card A and one NT8D09CAE5 (new H/W)- card B in the same IPE shelf/cabinet.
3. – three 500/analog phones, one connected to card A (TN1a) and two connected to the card B (TN1b, TN2b), normal definitions (CLS: DTN).

Action 1:
1. – connect a recording device (warning!, only battery operated) in parallel with TN2b (on MDF or phone socket).
2. – make a call between TN2b and TN2a or TN1a; release the call.
3. – make a call between TN2a and TN1a and remain in talk.

Result1: you can record this call with the recording device connected to TN2b.

Action 2 after Action 1:
1.- on the phone connected to TN2b make OFF/ON Hook.
2.- make a call between TN2a and TN1a and remain in talk.

Result2: you can NOT record this call with the recording device connected to TN2b

WARNING! If you apply the same scenario by switching the card A and card B the result is: it is NOT possible to record any call to the monitored port TN2b.
The card NT8D09AL (old type) is O.K.

OUR CONCLUSION:
1. – the analog line card NT8D09CAE5 type has a design (H/W or S/W) error !
The signal level presented to the port TN2b is about of 0.3 to 0.7mV, enough to be recorded with “regular” recording devices.
In this situation the CROSSTALK parameter is “at the limit”, about 75dB, comparing with the old card NT8D09AL where the measured crosstalk is over 80dB

 

[nessman]

Did you try swapping out the suspect line card with one that is known to work? Is it only that one particular card - or any CA vintage card you've come across. If so - what were the results. Bad cards do happen.

Are you sure there's no bridging between ports on the two cards as a result of years of wiring put in place or someone's carelessness?

 

[lucris]

Hi Nessman,

Thank you for your reply.
Unfortunately it is now safe that any CA vintage have this problem.
The problem was detected at one of our important customer to many PBX's: 61C, 11C, 1000E, S/W Release 4.5, 5.0, 6.0(they made some measurement in accordance to their security standard).
We succeed to reproduce the problem in our lab.
We tried to measure line to line crosstalk using the method indicated in ETS 300 001 standard/chap.10, pag40.
Our measurement for interports crosstalk was about 60dB, less than minimum 75dB as in Avaya/Nortel documents (transmission parameters).
The purpose of this forum post is like other users to do this test and confirm if necessary to raise the case to Avaya.

 

[nessman]

I would raise the issue with Avaya then.

 

[nessman]

For what it's worth, this was just announced by Avaya today:

NT8D09CAE5 Replacement

The NT7K20AAE6 – Extended Analogue Message Waiting Line Card is a new card which is replacing the NT8D09CAE5 card for all
future analogue line card demand in North America. The NT7K20AAE6 card material status is currently CR or controlled release.
This means that the card is only available for shipment to approved partners and customers.

 

[lucris]

Thanks Nessman, meanwhile I received the notification for the Avaya Bulletin 100135056.

Now our problem is how to solve this problem with the customer.
It is written in the bulletin "the card is used primarily in NA and has very limited use in other regions"; we are in EMEA region and only for this customer we talk of few dozen NT8D09CAE5 cards!

Do you have any good ideea for us?

 

[nessman]

Does the customer have a PASS account? Go through that channel first to see if they're aware of this problem. Otherwise, I'd swap them out with an earlier vintage.