[Asterisk-Users] How to ensure that software echo cancellation is on?

[jjones at quiddesign.com]

Per your readout it is off. A normally operating channel would look  
something like

Echo Cancellation: 128 taps, currently ON


You are restarting asterisk as you make changes and not just  
reloading right:)

On Jun 2, 2005, at 3:40 PM, Don Murray wrote:

>
> I have appended my /etc/asterisk/zapata.conf and my /etc/ 
> zaptel.conf files.  I am running Asterisk 1.0.7 on a P3 800 MHz  
> system in an office with around 20 sip phones.  We are using a  
> Digium Wildcard TE110P that is connected to a T1 line with 8 lines  
> enabled. We have been experiencing irritating echo on the sip phone  
> side when local lines are called.
> After reading a lot of echo related threads, I think I understand  
> the 4-wire to 2-wire cause of this echo.  I have noticed that when  
> calling long distance and with some cell phones there is no echo,  
> which is consistent with a system that has echo cancellation on the  
> destination end.
>
> So, I've been trying to enable software echo cancellation to see if  
> it will improve the situation.  If you look down to see my  
> zapata.conf file, you will see I've tried to set echocancel and  
> echocancelwhenbridged, and that I've also mucked around with  
> echotraining.  None of these appear to be doing anything.
> However, I *think* this is because they are not being enabled  
> properly, because when I try to see the details of an active zap  
> channel (see zap show channel command) it says "Echo Cancellation:  
> 0 taps unless TDM bridged, currently OFF".   I'm not sure if I'm  
> doing this debugging right, so I wanted to ask people both :
>
> (a) am I enabling echocancel correctly?  I've heard that sometimes  
> these parameters can behave differently depending on the order they  
> appear in the file??
>
> (b) am I doing the right thing to detect if echo cancellation is  
> on?  Whats the righ tway to do that?
>
> btw, I have rebuild my zaptel src with "AGGRESSIVE" cancellation  
> enabled, with MMX enabled and with MARK2 cancellation enabled.
>
> Any advice appreciated!
>
> Thanks,
> Don
>
>
>
> asterisk1*CLI> zap show channel 8-1
> Channel: 8CLI>
> File Descriptor: 32
> Span: 1
> Extension:
> Dialing: no
> Context: from-pstn
> Caller ID string: 520xxxxxxx
> Destroy: 0
> InAlarm: 0
> Signalling Type: PRI Signalling
> Owner: <None>
> Real: <None>
> Callwait: <None>
> Threeway: <None>
> Confno: -1
> Propagated Conference: -1
> Real in conference: 0
> DSP: no
> Relax DTMF: no
> Dialing/CallwaitCAS: 0/0
> Default law: ulaw
> Fax Handled: no
> Pulse phone: no
> Echo Cancellation: 0 taps unless TDM bridged, currently OFF
> PRI Flags:
> PRI Logical Span: Implicit
> Actual Hookstate: Onhook
> asterisk1*CLI>
>
>
> === zapata.conf
>
> [channels]
> language=en
>
> context=from-pstn
> switchtype = national
> signalling = pri_cpe
> group = 0
> channel => 1-8
> faxdetect=both
> ;;echocancel=yes
> ;;echotraining=yes
> ;echocancelwhenbridged=yes
> echocancel=256
> ;echotraining=800
>
>
> === zaptel.conf
>
> loadzone        = us
> defaultzone     = us
>
> span=1,1,0,esf,b8zs
> bchan=1-8
> dchan=24
>
> _______________________________________________
> Asterisk-Users mailing list
> Asterisk-Users at lists.digium.com
> http://lists.digium.com/mailman/listinfo/asterisk-users
> To UNSUBSCRIBE or update options visit:
>   http://lists.digium.com/mailman/listinfo/asterisk-users
>
>
>