sundance-communications.com/forum Forums TDM Business Telephone Systems Toshiba Telephones & Systems CTX100 IP phone echo

We have 4 i.p. phones that connect to our ctx-100 over the internet when you turn up the volume on a call the phone echos i tried both codecs g711a and the other one can't remember is there any other settings to stop the echo?

Strata CTX Echo Improvement Procedures
*** Procedure to improve echo on external call between analog trunk and IPT ***
Step 0. Hardware PAD on RCOU/RCOS
Default of hardware PAD on RCOU/RCOS is "0". So, please set it as "3", then make a couple of
calls to verify voice quality. This will be effective if the system is located closely to their carrier.
Please note that there are 4 switches on RCOU and 4 switches on RCOS, one switch is
associated to one port. Please confirm all of switches have been set as "3".
If echo still exists or you feel some issue on voice quality, please change those switches back to
"0" and move to step 1.

Step1. Add "3dB Loss" between IPT and analog trunk with Prog107
Prog107 FK1 Sender=10(IPT)
FK2 Receiver=3(analog trunk)
FK3 default value="1: -6dB(6dB Gain)" => Set "2: -3dB(3dB Gain)".
Prog107 FK1 Sender=3(analog trunk)
FK2 Receiver=10(IPT)
FK3 default value="3: 0dB" => Set "4: 3dB(3dB Loss)".
Prog107 FK1 Sender=10(IPT)
FK2 Receiver=7(Conf Bridge)
FK3 default value="1: -6dB(6dB Gain)" => Set "2: -3dB(3dBGain)".
Prog107 FK1 Sender=7(Conf Bridge)
FK2 Receiver=10(IPT)
FK3 default value="3: 0dB" => Set "4: 3dB(3dB Loss)"

Then, make a couple of external calls with RCOU3A to verify voice quality.
If you don't experience voice quality issue any more, your job at the site is over.
If the voice quality is still not acceptable, please follow the next procedure depending upon case
result.
Case A) Although echo disappears, volume is too low.
Then, take step2.
Case B) Although volume is OK, echo is still existing.
Then, take step3.
Case C) Echo still exists and volume is too low.
Then, take step4.

Step2. Change voice quality mode to Middle from High (default), and adjust PAD value as follows
Prog150 FK11 default value="1: High" => Set "2: Middle".
Prog107 FK1 Sender=10(IPT)
FK2 Receiver=3(analog trunk)
FK3 Confirm "2: -3dB(3dB Gain)" is there.
Prog107 FK1 Sender=3(analog trunk)
FK2 Receiver=10(IPT)
FK3 Set "3: 0dB".
Prog107 FK1 Sender=10(IPT)
FK2 Receiver=7(Conf Bridge)
FK3 Confirm "2: -3dB(3dB Gain)" is there.
Prog107 FK1 Sender=7(Conf Bridge)
FK2 Receiver=10(IPT)
FK3 Set "3: 0dB".
Then, make a couple of external calls with RCOU3A to verify voice quality.
If you don't experience voice quality issue any more, your job at the site is over.
If you hear echo again, please follow step 4.

Step3. Change voice quality mode to Middle from High (default), and add 3dB more for PAD table
as follows.
Prog150 FK11 default value="1: High" => Set "2:Middle".
Prog107 FK1 Sender=10(IPT)
FK2 Receiver=3(analog trunk)
FK3 current value="2: -3(3dB Gain)" => Set "0: 0dB".
Prog107 FK1 Sender=3(analog trunk)
FK2 Receiver=10(IPT)
FK3 Set "4: 3dB (3dB Loss)".
Prog107 FK1 Sender=10(IPT)
FK2 Receiver=7(Conf Bridge)
FK3 current value="2: -3(3dB Gain)" => Set "0: 0dB".
Prog107 FK1 Sender=7(Conf Bridge)
FK2 Receiver=10(IPT)
FK3 Set "4: 3dB (3dB Loss)".
Then, make a couple of external calls with RCOU3A to verify voice quality.
If you don't experience voice quality issue any more, your job at the site is over.
If you still hear echo or volume is too low, please follow step 4.


Step4. Change voice quality mode to Low, and adjust PAD table as follows.
Prog150 FK11 Set "3: Low".
Prog107 FK1 Sender=10 IPT
FK2 Receiver=3 analog trunk
FK3 Set "0: 0dB". <= It may be already 0dB depending on previous
procedure.
Prog107 FK1 Sender=3 analog trunk
FK2 Receiver=10 IPT
FK3 Set "0: 0dB". <= It may be already 0dB depending on previous
procedure.
Prog107 FK1 Sender=10 IPT
FK2 Receiver=7 Conf Bridge
FK3 Set "0: 0dB". <= It may be already 0dB depending on previous
procedure.
Prog107 FK1 Sender=7 Conf Bridge
FK2 Receiver=10 IPT
FK3 Set "0: 0dB". <= It may be already 0dB depending on previous
procedure.


Note:
After you follow step 4, you may feel voice quality is not good although echo disappears. To
completely remove echo trades off voice quality. So, please ask the customer, which is better, the
result of steps 1/2/3 or the result of step4. Toshiba usually recommends applying High as voice
quality mode in Prog153, and sometime Middle depending on the situation. But, if the customer
prefers the result of step 4 with "Low", you can leave it as the result of step 4

If you are using analog lines you will probably not get rid of the echo. You can minimize it by using high quality switches/routers and allowing up to 30 seconds for the call to adjust to conditions. You can't get any QoS over the internet and the analog phone lines don't help. VoIP works better with a PRI or a T-1 as your local service.

That's awesome it worked i used the -3db gain on prog107

- Thanks
Fitz