True, but you can make an apple pie taste better by adding a little orange juice....
Jim Shilliday -----Original Message----- From: Rich Adamson [mailto:[EMAIL PROTECTED] Sent: Tuesday, October 12, 2004 3:58 PM To: Asterisk Users Mailing List - Non-Commercial Discussion Subject: Re: [Asterisk-Users] Chaining more than one zap echo canceller? Impedance does not equal resistance. Apples and oranges. ------------------------ > If you're certain it is an impedance problem and the impedance of your > line is lower than that of the CO, you can increase the impedance of > your line by putting a potentiometer in-line and adjusting it until the > sidetone disappears. This is a bare-bones solution and decreases the > efficiency of the line because you're putting in pure resistance. > > If your impedance is higher than the CO, or if you want to be more > efficient, you'll need a more complicated impedance matching network. > > On Oct 12, 2004, at 10:26 AM, Kris Boutilier wrote: > > > I have Asterisk connected to a channel bank via a t100p card. There > > excessive sidetone generated on the analog side due to an impedance > > mismatch > > - I am very close to my serving CO which brings the line down to about > > 150ohms and the channel bank is expecting 600ohms. However, the very > > loud > > sidetone is being fairly effectively supressed by the zap echo > > canceller and > > I have quite usable lines as a result. > > > > From time to time calls are placed to other PSTN numbers (even > > terminating > > off of the same CO) that are introducing their own far end echo > > component on > > the line and it isn't being supressed at all - thus my outbound callers > > begin to hear thei rownvoiceandgetveryfrustrated.Ihaveto > > assume the > > second reflection couldn't be supressed by design - the zap echo can > > has > > already locked on to the sidetone echo after all. > > > > So, I have a fix for the sidetone/impedance problem (PRI on order) > > however > > is it possible to insert another can into the system somehow? For > > example, > > if I were to run TDMoE to a second box and access to the t100p/channel > > bank > > through there? > > > > Any suggestions welcome (apart from curing the sidetone) :-) > > > > Kris Boutilier > > Information Systems Coordinator > > Sunshine Coast Regional District > > > > _______________________________________________ > > Asterisk-Users mailing list > > [EMAIL PROTECTED] > > http://lists.digium.com/mailman/listinfo/asterisk-users > > To UNSUBSCRIBE or update options visit: > > http://lists.digium.com/mailman/listinfo/asterisk-users > > _______________________________________________ > Asterisk-Users mailing list > [EMAIL PROTECTED] > http://lists.digium.com/mailman/listinfo/asterisk-users > To UNSUBSCRIBE or update options visit: > http://lists.digium.com/mailman/listinfo/asterisk-users ---------------End of Original Message----------------- _______________________________________________ Asterisk-Users mailing list [EMAIL PROTECTED] http://lists.digium.com/mailman/listinfo/asterisk-users To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users _______________________________________________ Asterisk-Users mailing list [EMAIL PROTECTED] http://lists.digium.com/mailman/listinfo/asterisk-users To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
