I thought that if the VPM was detected then you didn't have any control as to which algorithm was used.
I was under the impression that the algorithms were only used for the software echo cancellation. At this point I'll give anything a try. Stagg Shelton www.oneringnetworks.com -----Original Message----- From: Rob Lith <[EMAIL PROTECTED]> Subj: Re: [Asterisk-Users] TE411P Really Bad Echo Date: Sat Feb 11, 2006 10:17 am Size: 4K To: Asterisk Users Mailing List - Non-Commercial Discussion<asterisk-users@lists.digium.com> Stagg I don't think it's a matter of trying echocancel on and off, it is a matter of tuning your system to your local PSTN - this is a combination of trying the different echocan alogrithims (i.e. MG2), the echotrainign etc and setting your txgain - too loud outgoing audio will result in echo. http://www.asteriskdocs.org/modules/tinycontent/content/docbook/current/docs-html/x1695.html#AEN1718 Rob On 2/11/06, Stagg Shelton <[EMAIL PROTECTED]> wrote: > > Yes, right now we are only using span 1 on the quad span card with plans > to pull in another T1 PRI when we get this echo problem solved. The echo is > only experienced when the call terminates to traditional analog circuits > both local and long distance. Calls to cell phones, and other known digital > circuits do not exhibit the symptoms. I've been sent a few articles off > list which discussed the reasons why this may occur, imperfect impedance > where the digital circuit is switched to the analog circuit. > > In testing I've set echocancel=no made calls, and echocancel=yes and made > calls with no real audible difference. I haven't done a zap show channel > while on a call with echo, but I plan to this weekend. I was informed that > the number of taps would be shown. I used a stop watch last night to try to > get the delay, and it was about 1/2 to 1 second delay and was continual so > long as I was talking. It wasn't affected by differing acoustical > variations. I tested this using handset, headset, and speakerphone. > Disabling VPM and recompiling zaptel or removing the VPM off the board > completely is the only thing that has any effect on the echo. Hopefully the > zap show channel will provide to me another data point to help me determine > if the HW module is active. > > More to come... > > Stagg Shelton > www.oneringnetworks.com > > > Cory Andrews wrote: > > Stagg - I know you get a full 128ms tail of echo can on the Sangoma. I > believe that on the TE411P, the 128ms tail is shared by all (4) spans, and > as you add additional spans up to maximum of 4, the echo can tail amount > decreases accordingly. If you are running 4 spans, you have 32ms of echo > can tail on each span, not the full 128ms. > > Now that I'm reading back through your post thread, it looks like you were > only running 1 span on the TE411P, so you should have been getting the full > 128ms of echo can tail. You may not find an improvement with the Sangoma. > I have never experience, nor heard of a 1-2 full second delay. Trial and > error is likely your course of action. > > Cory J Andrews > ++++++++++++ > VOIPSupply.com > 454 Sonwil Drive > Buffalo, NY 14225 > ++++++++++++++ > voice - 716.630.1555 X22 > email - [EMAIL PROTECTED] > AIM - B2CORY > > ----- Original Message ----- > *From:* Stagg Shelton <[EMAIL PROTECTED]> > *To:* Asterisk Users Mailing List - Non-Commercial > Discussion<asterisk-users@lists.digium.com> > *Sent:* Friday, February 10, 2006 11:34 PM > *Subject:* Re: [Asterisk-Users] TE411P Really Bad Echo > > It was Digium's opinion that perhaps the card had a VPM. We got a > replacement TE411P, I implemented it tonight and still the exact same echo > problem. At this point I feel like I can rule out failed hardware. > > I contacted Digium support and now they are telling me it's something with > my carrier, and I should call them. I called Bellsouth, and they ran a full > stress test on the circuit taking me offline for about 30 minutes. > > The end result is that the circuit test passed with no errors. Bellsouth > says it's not in their network, Digium says its not their card, and I have a > te411p with VPM disabled in the wct4xx kernel module because something > doesn't work the way it should. My customer is wanting to know about > sangoma cards with the echo cancellation, and at this point I'm nervous to > recommend any hardware. I'm going to look into the sangoma that you > suggested. Are there any other kinds of products that I could look into > either Passive or Active. > > Thanks > > Stagg Shelton > www.oneringnetworks.com > > > Matt wrote: > > try sangoma carrier grade 104d hardware EC card. we're using it ourself. > > Best Regards > > Matt > ----- Original Message ----- > From: "Anthony Rodgers" <[EMAIL PROTECTED]> <[EMAIL PROTECTED]> > To: "Asterisk Users Mailing List - Non-Commercial Discussion" > <asterisk-users@lists.digium.com> <asterisk-users@lists.digium.com> > Sent: Tuesday, February 07, 2006 12:57 PM > Subject: Re: [Asterisk-Users] TE411P Really Bad Echo > > > For what it's worth, we have been going through very similar issues > with a --- message truncated --- _______________________________________________ --Bandwidth and Colocation provided by Easynews.com -- Asterisk-Users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users