I figured I'd answer my own thread and document what it took to get rid of the echo at my location. For those of you trying to get rid of echo, let me tell you, "what worked for that guy, probably won't work for you". I think we've all heard that before, and it's true. Let me assure you that echo can be removed from your phone lines. At 20 hours into my 40 hours spent purging echo from my system, I didn't believe that, but its true. So, here's what it took to get it out of my system: 1. Download zaptel-trunk from SVN: As of this writing (6/20/06) using the "trunk" code instead of the 1.2.6 code was a major contributor in getting my echo to go away. 2. Use fxotune in zaptel-trunk: Find a silent-termination test number from the phone company and use FXOTune. I couldn't get it to dial right in order to get silence on the line. You can verify if it's working correctly by running it with an analog handset connected to your phone line. Pickup the handset and then run the command. In my case, fxotune would never clear the line, or dial the silent termination number I was giving it, not sure if this is a bug or not. What I eventually had to do was pick up the phone, dial the silent-termination number manually, run "./fxotune -i -b 4 -e 4", and quickly hangup the phone. This was the only way I got good results from the program. 3. Patience and lots of "vi zconfig.h": Try each echo canceler, with and without the "Aggressive" option. What eventually worked for me was the MG2 with Aggressive cancelation. 4. Along with above, you need to also try each and every combination of echocancel=xx and echotraining=xx. These setting do make a difference. I went through every possible value of each setting with each echo canceler, and kept notes along the way. 5. TIME: As I said above, I probably have 40 hours into eliminating the echo, but it is genuinely gone. Your echo problem can be solved, it will just take some time. Hope this helps someone! Thanks, Brian
I eliminated my echo almost instantly by purchasing an echo canceling card :) I had about 30 minutes into to get the card installed and asterisk up and running. On 6/20/06, Brian Swan <swannie@swannie.net> wrote:> I figured I'd answer my own thread and document what it took to get > rid of the echo at my location. For those of you trying to get rid > of echo, let me tell you, "what worked for that guy, probably won't > work for you". I think we've all heard that before, and it's true. > Let me assure you that echo can be removed from your phone lines. At > 20 hours into my 40 hours spent purging echo from my system, I didn't > believe that, but its true. So, here's what it took to get it out of > my system: > > 1. Download zaptel-trunk from SVN: As of this writing (6/20/06) > using the "trunk" code instead of the 1.2.6 code was a major > contributor in getting my echo to go away. > > 2. Use fxotune in zaptel-trunk: Find a silent-termination test > number from the phone company and use FXOTune. I couldn't get it to > dial right in order to get silence on the line. You can verify if > it's working correctly by running it with an analog handset connected > to your phone line. Pickup the handset and then run the command. In > my case, fxotune would never clear the line, or dial the silent > termination number I was giving it, not sure if this is a bug or > not. What I eventually had to do was pick up the phone, dial the > silent-termination number manually, run "./fxotune -i -b 4 -e 4", and > quickly hangup the phone. This was the only way I got good results > from the program. > > 3. Patience and lots of "vi zconfig.h": Try each echo canceler, with > and without the "Aggressive" option. What eventually worked for me > was the MG2 with Aggressive cancelation. > > 4. Along with above, you need to also try each and every combination > of echocancel=xx and echotraining=xx. These setting do make a > difference. I went through every possible value of each setting with > each echo canceler, and kept notes along the way. > > 5. TIME: As I said above, I probably have 40 hours into eliminating > the echo, but it is genuinely gone. Your echo problem can be solved, > it will just take some time. > > Hope this helps someone! > > Thanks, > Brian > _______________________________________________ > --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 >
On Tuesday 20 June 2006 11:30, Brian Swan wrote:> 3. Patience and lots of "vi zconfig.h": Try each echo canceler, with > and without the "Aggressive" option. What eventually worked for me > was the MG2 with Aggressive cancelation.I hate to tell you this, but if you have turned on the aggressive suppressor you aren't cancelling echo. You have turned your phone into a half-duplex communication medium. With the aggressive suppressor enabled, when zaptel detects you talking, it MUTES the received audio. Try it -- call up a friend and ask him to burp the alphabet. While he's doing that, talk to him. You will stop hearing him whenever you talk. -A.
On Wednesday 21 June 2006 03:30, Brian Swan wrote:> 2. Use fxotune in zaptel-trunk: ?Find a silent-termination test ? > number from the phone company and use FXOTune. ?I couldn't get it to ? > dial right in order to get silence on the line. ?You can verify if ? > it's working correctly by running it with an analog handset connected ? > to your phone line. ?Pickup the handset and then run the command. ?In ? > my case, fxotune would never clear the line, or dial the silent ? > termination number I was giving it, not sure if this is a bug or ? > not. ?What I eventually had to do was pick up the phone, dial the ? > silent-termination number manually, run "./fxotune -i -b 4 -e 4", and ? > quickly hangup the phone. ?This was the only way I got good results ? > from the program.I had that problem too, it's a bug, see 7264 on mantis. hads -- Two wrongs don't make a right, but three lefts do.