Retransmission of noise in analog ports

[petran]

Hello,

We faced a problem recently were a customer had a voice recording system connected to a definity through analog ports, which was activated when voice signals came through that port.

The voice recording system used to activate itself randomly for no apparent reason. We tested and found out the following:
When a user dialed any outside number and the call went through Analog CO trunks, the definity retransmitted any voice signals within the first 0.5 sec after connection to every analog port in the system! This caused the voice recording system to activate and record what at first sounded like noise, but then was crearly voice!!

We tested with various s/w releases, CO Trunk boards, Analog port boards etc. Only CMC carriers do not allow the retransmition no matter what release the system is.

Has anyone seen this before ?

Thank you. Petran.

 

[G van Hamburg]

Hi Petran,

Seems to me you're the vendor of the voice recording system and you're testing it with Definity. You mentioned you've tested with different releases so I guess Avaya is helping you.

Tell them that this problem indicates a TDM problem and that that they should do some tests.

Let them do a "test po xxx" and look for test 6. This is the cross talk test. It seems like the tdm bus, tone board or expansion interface has a problem.

If you have just one switch, look if the TDM bus connectors are in place and none of the pins are bent.

You can also do another test.

Try the CMC with just one TDM bus terminator and see if the problem occurs. Plan your work............Work your plan

 

[petran]

Hi,

we are the vendor of the Definity. We suspected a TDM problem. Avaya technical personel could find no answer and we could not perform the tests they asked at customer site (the customer was unwilling to let us play with their system).

We tested in our labs with different carriers, s/w loads, processors, terminators, boards etc. and the problem remains. It looks like a design fault but Avaya was not so willing to check it. Petran.

 

[G van Hamburg]

Ok,

All the previous information can be found on the maintenance CD.

Just see if you can reproduce the problem on a CMC and then escalate the problem as if it's your own system.

Last thing you could try is galvanic rings. This can prohibit cross talk when all the cables are right to each other.

You can get these in a electronics shop. Plan your work............Work your plan

 

[netcon1]

I assume the voice activated switch or recorder is picking up the slightest noise and recording that as information.

Does the mainteneance test option on the analog station have any affect on this situation. Have you turned it of on each port/station on the card you are testing?

One idea might be...

If you are a vender, you are probably seeing backplane to Amphenal twisted pair cable kits coming for you C-lan card/Medpro. This cable kit is a 100Mbps Cat 5 cable assembly, that has to be swapped into the cabinet for the clan/medpro card for 100Mbps support.

It has tighter twisted on it to reduce crosstalk.(CAT5 rating)

What if you tried,in your test system, to replace the slot conector in question with one of these items, and see if the problem goes away.

the part number is 700234032
Name: Def Kit Twisted Pair CBL for 100Mbps.
worth a shot if you have one.

Netcon1

 

[petran]

Hi,

netcon1,

The recorder indeed records the slightest noise.
The problem appears on ports even if they are not adninistered. If you connect an analog set to an unadministered port, pick up the handset, and someone dials at that time, you can hear the noise. (with Greece's country settings the 0.5 sec becames 2 sec. The 0.5 sec interval was in Hungary were Avaya Labs tested. In Greece we hear the called party saying "hello..."!!!!!)

We have already tried everything possible with wiring with no effect. Problem remains (we even connected the analog set through a short shielded CAT 5 cable. No luck!!!. we tried with direct thin wires the Public Provider uses for long distance networks, problem remains!!)
Petran.