Old fashioned echo or hollowing sounding circuits generally were due to mismatches somewhere. There was singing high and singing low and other measurements that were essentially return loss tests. Having a transmit level too high was a sure fire way to create a hollow sounding circuit.
I am guessing latency is your problem. I doubt that is an impedance mismatch between the ATA hybrid/SLIC circuit and the phone. From: Chris Fabien Sent: Saturday, February 17, 2018 8:22 PM To: [email protected] Subject: Re: [AFMUG] How to create echo on an analog tel line So we had a customer complaining about sometimes hearing an echo, they go get a new multi handset dect cordless phone system, and it's now way worse echo than the old phone. We are using the built in ATA in our ZTE ONU, never had much trouble with echo on the Cisco ATA we used to use on wireless customers. Not sure how to address this or just give up in the ZTE go up if it's just crap? On Feb 17, 2018 8:26 PM, "Adam Moffett" <[email protected]> wrote: You can get acoustic echo by adding latency. This is the handset mic picking up the handset speaker, and it doesn't happen on POTS lines, but it happens on VoIP using the exact same phone because the up and down path are no longer synchronous. There are also electrical echo effects that are above my pay grade. One of the old phone guys here maybe knows something. My understanding is that echo cancellation can detect and fix the electrical echos, but not the acoustic echo. To fix acoustic echo you either turn down the volume on the handset or use a different handset. ------ Original Message ------ From: "Chris Fabien" <[email protected]> To: [email protected] Sent: 2/17/2018 6:09:32 PM Subject: [AFMUG] How to create echo on an analog tel line We are having sporadic reports of our subscriber hearing an echo on some new go up ATA we are usin g. Whenever I test it myself with various phones, it's fine. Anyone know how I can create this condition so I can fool with the echo cancellation gains to see if I can fix it?
