I'd say the problem arises when the duration of the generated digits is not sufficient to allow the far end to determine that it has, in fact, heard a touch tone digit and not some background noise having a similar harmonic.
One of the challenges an IVR has to handle is a problem known as talk-off. This condition occurrs when the DTMF detection is too sensitive, and thus frequencies normally present in the human voice cause the system to think a digit has been pressed. If the system being called has a fairly long DTMF detection minimum ( to avoid talk-off), and the unit generating the DTMF generates a tone of too short a duration (presumably in an effor to reduce the time required to dial a number), and the quality of one or more ananlogue loops involved in the circuit is poor, then the chances of missed digits is fairly large. Jim. -- Jim Van Meggelen [EMAIL PROTECTED] http://www.oreillynet.com/pub/au/2177 "A child is the ultimate startup, and I have three. This makes me rich." Guy Kawasaki -- > -----Original Message----- > From: Reza - Asterisk Enthusiast [mailto:[EMAIL PROTECTED] > Sent: February 19, 2006 1:29 PM > To: TAUG > Subject: Re: [on-asterisk] Persistent DTMF Issue > > Hello Jim! > > I always like a good mystery. For whavetever reason it is, > it is obvious > that DTMFs are not transmitted correctly at the other end for > it to be interpreted. Theoritically speaking, why do you > think this issue persists with Ian's system? > > Ian: If you have any luck, I'd love to hear from you. > Please keep us > posted with this DTMF thingy. > > Cheers! > > Reza. > > ----- Original Message ----- > From: "Jim Van Meggelen" <[EMAIL PROTECTED]> > To: "'Reza - Asterisk Enthusiast'" <[EMAIL PROTECTED]>; "'TAUG'" > <[email protected]> > Sent: Sunday, February 19, 2006 11:52 AM > Subject: RE: [on-asterisk] Persistent DTMF Issue > > > > The difference between "RFC2833" and "Info" in the Sipura > is lost on me. > > As > > far as I have been able to determine, they're the same thing. > > > > Jim. > > > > -- > > Jim Van Meggelen > > [EMAIL PROTECTED] > > http://www.oreillynet.com/pub/au/2177 > > > > "A child is the ultimate startup, and I have three. > > This makes me rich." > > Guy Kawasaki > > -- > > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [EMAIL PROTECTED] > For additional commands, e-mail: [EMAIL PROTECTED] > > > > -- > No virus found in this incoming message. > Checked by AVG Free Edition. > Version: 7.1.375 / Virus Database: 267.15.11/264 - Release > Date: 17/02/2006 > > -- No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.1.375 / Virus Database: 267.15.11/264 - Release Date: 17/02/2006
