Claus Tondering <ct@dde.dk> (05/16/91)
I frequently phone the US from Europe; but I often run into trouble if the party I am calling asks me to enter some number (e.g. an extension number or a menu selection) on my touch-tone phone. Although the touch-tone frequencies are international, these selections often do not work when used from Europe. One of three things happens: 1) It works perfectly, and I get connected as requested. 2) It works only if I hold each key down for two or three seconds. 3) Absolutely nothing happens. The American party does not recognize my touch-tones. I have even noticed both behavior 2 and 3 when calling the same (Massachusetts) number on different occasions. Why this difference in behavior? What can I do to make it work always? Where does the fault lie? In Europe? In the US? In the satellite? Claus Tondering E-mail: ct@dde.dk Dansk Data Elektronik A/S, Herlev, Denmark
hullp@cogsci.Berkeley.EDU () (05/20/91)
In article <telecom11.373.2@eecs.nwu.edu> Claus Tondering <ct@dde.dk> writes: > I frequently phone the US from Europe; but I often run into trouble if > the party I am calling asks me to enter some number (e.g. an extension > number or a menu selection) on my touch-tone phone. Although the > touch-tone frequencies are international, these selections often do > not work when used from Europe. One of three things happens: > 1) It works perfectly, and I get connected as requested. > 2) It works only if I hold each key down for two or three seconds. > 3) Absolutely nothing happens. The American party does not recognize > my touch-tones. > I have even noticed both behavior 2 and 3 when calling the same > (Massachusetts) number on different occasions. I have had similar problems in getting my US tone-controlled answering machine to play back messages from overseas phones. I've had such problems both with foreign phones *and* using a Radio Shack pocket tone generator (where there's no touch-tone phone available) from Spain, the UK, and from Guatemala. I *think* the problem is simply poor lines on which tones don't have a high enough volume (or maybe the frequencies get messed up?). The only solution I've found is the same as your #2: To hold the button down for several seconds. For this reason, I don't like phones (such as many Panasonic models) on which the length of time each tone is generated is automatically controlled i.e., if you hold the button down the tone is *not* generated continuously until you take your finger off. Philip V. Hull INTERNET: hullp@cogsci.berkeley.edu BITNET: hullp@cogsci.berkeley.bitnet UUCP: ucbvax!cogsci!hullp OR: ucbvax!cogsci.berkeley.edu!hullp
John Higdon <john@zygot.ati.com> (05/20/91)
Claus Tondering <ct@dde.dk> writes: > One of three things happens: > 1) It works perfectly, and I get connected as requested. > 2) It works only if I hold each key down for two or three seconds. > 3) Absolutely nothing happens. The American party does not recognize > my touch-tones. > Why this difference in behavior? What can I do to make it work always? > Where does the fault lie? In Europe? In the US? In the satellite? This could very well be the result of "twist", the reception of the component tones of a DTMF at unequal levels. While the DTMF frequencies fall squarely in the "voice" band of a telephone channel, sometimes the circuit will have a non-flat frequency response characteristic. This means that on a single digit, the high tone may be detected at a significantly different level than the low tone. Such a condition usually results in the non-registering of the digit. Holding the button down and extending the length of the tone will sometimes work because the receiver can occasionally adapt to the condition while the tone is sounding. Otherwise, you would probably have to hang up and get another circuit. John Higdon | P. O. Box 7648 | +1 408 723 1395 john@zygot.ati.com | San Jose, CA 95150 | M o o !