martin@trout.nosc.mil (09/01/89)
I am interested in finding literature references on how the various telephone sounds, e.g. dial tone, busy signal, and the decaying tone associated with credit card calls, were chosen. What kinds of psychoacoustic research were done to determine that these sounds are easily remembered, easily discriminated in noise, or less annoying than other sounds which could have been selected. I am looking for references on how these sounds were selected. Thanks, Doug Martin martin@nosc.mil
martin@cod.nosc.mil (Douglas W. Martin) (12/09/89)
I posted this request several months ago, but got no response.
Anyone with any ideas or speculations is greatly appreciated.
I am interested in finding literature references on how the
various telephone sounds, e.g. dial tone, busy signal, and the
decaying tone associated with credit card calls, were chosen. What
kinds of psychoacoustic research were done to determine that these
sounds are easily remembered, easily discriminated in noise, or less
annoying than other sounds which could have been selected. I am
looking for references on how these sounds were selected.
Also, can anyone supply information about the frequency,
duration, etc. for the off-hook alarm signal?
Thanks,
Doug Martin
martin@nosc.milMiguel_Cruz@um.cc.umich.edu (12/10/89)
Doug Martin (martin@nosc.mil) asked in digest 9.561 about the tone the phone company blasts out when you leave your receiver off-hook for too long. As far as I know, it's 1400 Hz + 2060 Hz + 2450 Hz + 2600 Hz simultaneously, cycled on and off every .1 seconds. [Moderator's Note: But, I believe his question was, how were these sounds chosen? Did a committee somewhere listen to various sounds and choose this as the most appropriate? When and how were they picked? PT]
tell@oscar.cs.unc.edu (Stephen Tell) (12/11/89)
A related question on choice of tone signals: Has anyone else noticed that a lot of people in the "general public" (non-telecom-junkies) can't tell the difference between a busy and a reorder, or maybe don't know to listen for the difference in interuption rate? I'm still in touch with a lot of people at Duke University, where I used to be a student, but now I'm just beyond the area that is a local call for people on campus. It has happened many times that someone has tried to call me from a restricted campus phone (local-only, like a public non-coin phone), and complained "Your line is always busy." The Duke phone system (their own 5ESS) gives reorder for this case, also for the case of dialing only 7D when 1+7D is required. The latter may be more the problem, since GTE in Durham (around Duke, off-campus) doesn't want the leading 1. I explain "that's not a busy signal" and get funny looks from people who never heard of reorder, but I wonder how many calls I miss this way? (Perhaps this is an item for RISKS?) Steve Tell tell@cs.unc.edu CS Grad Student, UNC Chapel Hill. Former video guy, Duke Union Community Television, Durham, NC.
segal%cell.mot.COM@uunet.uu.net (Gary Segal) (12/12/89)
martin@cod.nosc.mil (Douglas W. Martin) writes: > Also, can anyone supply information about the frequency, >duration, etc. for the off-hook alarm signal? The off-hook warble tone comes on after about 18 seconds. It is a composite of a 1400Hz tone and a 2060Hz tone at about -12dBm. It is on for 0.1 second and then off of 0.1 second. While I'm at it... Ringback is 440Hz & 480Hz, 2.0 seconds on, 4.0 seconds off, -12dBm. Busy is 480HZ & 620Hz, 0.5 sec on, 0.5 sec off, -12dBm. Reoder is busy twice as fast (0.25 on, 0.25 off). Off course, the above is only sometimes true, and only then in the USA. Gary Segal, Motorola C.I.D. 1501 W. Shure Drive ...!uunet!motcid!segal Arlington Heights, IL 60004 Disclaimer: The above is all my fault. +1 708 632-2354
john@bovine.ati.com (John Higdon) (12/15/89)
tell@oscar.cs.unc.edu (Stephen Tell) writes: >The Duke phone system (their own 5ESS) gives reorder for this case, also for >the case of dialing only 7D when 1+7D is required. The latter may be more the >problem, since GTE in Durham (around Duke, off-campus) doesn't want the >leading 1. >I explain "that's not a busy signal" and get funny looks from people who >never heard of reorder, but I wonder how many calls I miss this way? >(Perhaps this is an item for RISKS?) Hasn't an organization the size of Duke University heard of intercept recordings? It's not at all surprising that people are confused by getting a reorder every time they do something wrong. A reorder conveys little useful information to the caller except the absolute assurance that the call isn't going through. Here in PacTelLand, tariffs forbid you, as a DID subscriber to simply have invalid numbers go to reorder. You MUST have an intercept recording, preferably with SIT. Pac*Bell (and GTE, although they're more used to it) got tired of having tons of "call fails" rack up on their network tally devices. Since the lines are monitored for busies, reorders, and SITs, a high number of reorders looks real bad. Even on the PBXs that I tend, I use the ARS to send wayward calls to various Pac*Bell intercept recordings, which are available in a convenient bank of non-supervising numbers. Tell the telecom administrator at the university that the telephone users are not psychic and need to be given a clue as to why their calls fail. John Higdon | P. O. Box 7648 | +1 408 723 1395 john@bovine.ati.com | San Jose, CA 95150 | M o o !