Solved - ObiLine in Israel

[mrjoe]

I'm using the ObiLine in Israel and it has a terrible Echo.

Anyone know the ACI Impedance?

I have tried all of them but every choice produces echo, some more some less.

Obi support told me to change the TX Gain on the phone ports but I don't want to start that before I have found the best setting for ACI Impedance.

anyone?

[ianobi]

This document seems to be about testing telephone equipment for connection to Israel's PSTN:

http://www.moc.gov.il/sip_storage/FILES/8/388.pdf

It quotes a reference impedance of 270 + (750||150nF) which is one of the OBi options.

If you are getting echo for all settings, then there is a more practical approach. The more echo you are getting the worse must be the impedance mismatch between the OBiLINE and the PSTN line it is connected to. You cannot change the impedance of the PSTN line, so if you change the OBiLINE impedance until you get the least echo, then you have the best impedance match.

[mrjoe]

Thank you so much Ianobi, you're being a great help.

I will try it out when I get home.

[mrjoe]

Hi Ianobi - thank you for finding that for me.

The echo is barely noticeable on that setting.

Have a nice weekend!

[JR20]

Hi,

thanks for all of the legwork.

I too have my OBiLine overseas and tested "270 + (750||150nF)"

It worked for me and it fix 98% of my echo issues on POTS.

I was curious what the specifications were for the phone system in the country that i'm in and found this great document that lists most of the specifications of POTS systems in the world:

https://supportforums.cisco.com/sites/default/files/legacy/5/0/7/44705-SPA400Configuration_060109.pdf

Best regards,
JR