Subject: Re: [asterisk-dev] DTMF length (Re: [svn-commits] russell:, branch 1.4 r61763 - /branches/1.4/main/channel.c)

Freddi Hansen fh at
Tue Apr 24 10:57:51 MST 2007

the values 80/45 is what i usually patches our systems to.
the value 80 is high enough to allow 'dtmf cut-through' on most IVR 
system. People often raise the 'on-time' detection to 60-65 ms increase 
'talk-off detection',  false hits from background noise etc.
If the cycle time (80+45) is higher than 125 ms then a lot of alarm 
system won't work, the ones I have tested sends 6-8 digit per seconds.
So the 80/45 sounds great to me. thanks.

> asterisk at wrote:
>> > So my vote is to drop it to 80ms tone and force a 45ms delay until the next
>> > DTMF digit as part of the total time (if it could be done that way).
> Thanks for the feedback!  I will work on it right now.  I will change 
> the minimum digit length to 80ms, and enforce a gap of at least 45ms 
> between digits.

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