Summary:ASTERISK-08049: Signalling levels - TBR21 :- the difference level of high frequency group and low frequency shall be 1 ..
Reporter:hashish (hashterix)Labels:
Date Opened:2006-11-02 07:48:12.000-0600Date Closed:2006-11-28 14:02:01.000-0600
Versions:Frequency of
Description:As per the TBR21 Manuals,

The level of the tone in the high frequency group shall be 1 to 4 dB higher than the level of the tone in the low frequency group.

We have a detailed test of DTMF produced by Asterisk on a Digium Card tdm400p for a Goverment Agency approval, we noticed that the Difference between Higher and Lower Frequency group is less than one. I have changed the country code etc .. But still showing the same. Where should be look into this issue? How can we accoplish this?
Comments:By: Serge Vecher (serge-v) 2006-11-08 16:03:17.000-0600

hashterix: I think this sort of problem is best handled through Digium Technical support directly at support@digium.com.

By: chankm (chankm) 2006-11-10 08:42:51.000-0600

Hi hashterix,

You might want to refer to ../zaptel/gendigit.c.

In gendigit.c, there are settings for LEVEL_DTMF_LOW and LEVEL_DTMF_HIGH.
The default value is set to -10 for both levels. This would explain why you
are getting a difference of less than 1. You might want to try changing the levels for e.g. for LEVEL_DTMF_HIGH = -8.

By: Matthew Fredrickson (mattf) 2006-11-28 14:02:01.000-0600

Should be handled through tech support