bcm50 rls1 echo 1

[jsaad]

I have a rls 1 bcm50 with Ip telephones and analog trunks, we just migrated from a PRI. There is an echo on the phone lines when you make a call through the IP phones. The digital phones are fine. The echo goes away after about a minute or two.

I was told to adjust the lines to shortCO LongCO MediumCO, ShortPBX and LongPBX. I tried all of them and switched from 600 to 900 ohm for impedance and it may no difference.

is a patch required?

 

[oldestgeek]

I would suggest an upgrade as echo was handled better in newer releases. Did you try the echo stopper devices I suggested?

 

[pkellow]

BCM050.SmartUpdate.System.008-200806 includes BCM050.182-CORE which includes the following fix:

- Line Tuning For BCM 50 R1
This update introduces the line tuning feature for the BCM 50 R1 product.
Q01475421-05


Have you already applied this? If not, please backup the BCM and apply it. Note: You will need to disable and enable the relevent BUS for the GATI or GATM (plain speak - GATI is the Global Analogue Trunk Interface on the main unit, GATM is a module in an expansion unit).

Everytime you physically remove a line, you'll need to reenable the bus. This implements adaptive line tuning, where BCM will try to tune the lines.

I once wrote solution 1038911 for this (available on

http://www.nortel.com)

albeit for 50r2. The symptoms were similar.

Failing this latest service update, you'd need to look at upgrading to 50r6 (not a one step upgrade), then retry. Even then you might need to look further at tuning your lines yourself....a little history.


On early BCM versions, the country profile was designed for that particular country. i.e. UK met the analogue
requirements for the UK.

(For example, I worked on problems in Turkey, before there was a country profile for Turkey. PRC (Peoples republic of China) improved things because they were a closer match for the actual lines than using a global or UK country profile.

You did not note the country profile you are using or the country the BCM is based in.....these are very relevent.)


Continuing the history....later, adaptive line tuning was introduced, allowing some automatic line tuning. This was made available in a patch (BCM050.182-CORE or later for release 1)


Later still (bcm50r3 or later, bcm450r1 or later), Programmable Application Interface was introduced where you could (in theory) line tune yourself under system->"Telephony Regions" within Business Element Manager. Easier said than done, you'd proabably need an incountry engineer to tune. Theoretically, you'd tune the lines, and then submit a request to Nortel to have this implemented. For example, if I look at a 450r5, under System->Telephony Regions, I currently see:
Colombia
Germany
Ireland
South Korea
Swiss
UAENA
UAE
Venezuela


Hope this helps

regards
paul

 

[jsaad]

this BCM is in the USA

 

[jsaad]

i have not tried that patch, I suppose I would have to be sure that it is not already patched, if not I will try to get this patch and give it shot!

silly thing is, if the customer just switched to t7316e or other digital phones we would not have to worry about patches or echos.

 

[pkellow]

Don't forget, after you've applied it, you would need to disable and enable the relevent bus for the GATI/GATM. Or reboot the BCM. Don't just apply it.