slf@lll-crg.llnl.gov (Sharon Lynne Fisher) (09/21/89)
I moved a couple of months back, and I've had a weird problem since then. I
get lots of wrong numbers. Some of them are the normal "Is Joe there?" and
I say no and the person goes away. But the vast majority of them have no
voice at all. I pick up the phone, hear a faint 'clickclickclick' in the
background, and nothing happens, so I hang up. On my answering machine,
I don't get any message either; just those faint sounds. I thought perhaps
it was people calling me from a computer, but then I'd hear a modem tone,
wouldn't I? Incidentally, I get these calls both long-distance and local.
Anybody have any idea what's going on?
If you're going to respond by mail, please reply to
sharon@asylum.sf.ca.us rather than to the address on this header. Thanks.
"Goldfish are quiet, under the water.
Girls who keep goldfish are often quite noisy."
-- The Jazz Butcher
[Moderator's Note: But we prefer replies here, so if you write Sharon, please
copy the Digest. Thanks. PT]eli@chipcom.com (09/22/89)
Sharon asked who (or what) might be calling her phone number and then not talking (or "tone"-ing"). My guess is that someone has published her phone number incorrectly as a FAX number. When fax machines initiate a call, they first *listen* for a faxmodem tone from the line they have called. If no tone is heard, they just hang up. (I think.) So, Sharon -- you might try plugging in a fax machine into your line during the periods when you receive these mystery calls. If a fax comes through, you'll be able to track down the company who published your number as their fax number. -- Steve Elias -- eli@chipcom.com (for Chipcom / networking related mail) -- eli@spdcc.com (for metroboston email2fax and personal mail) -- voice mail: 617 932 5598 -- work phone: 617 890 6844
dritchey@ihlpb.att.com (Donald L Ritchey) (09/23/89)
Summary: well!slf@lll-crg.llnl.gov (Sharon Lynne Fisher): In article (Message-ID: <telecom-v09i0393m03@vector.dallas.tx.us>), you wrote > X-TELECOM-Digest: volume 9, issue 393, message 3 of 11 > I moved a couple of months back, and I've had a weird problem since then. I > get lots of wrong numbers. Some of them are the normal "Is Joe there?" and > I say no and the person goes away. But the vast majority of them have no > voice at all. I pick up the phone, hear a faint 'clickclickclick' in the > background, and nothing happens, so I hang up. On my answering machine, > I don't get any message either; just those faint sounds. I thought perhaps > it was people calling me from a computer, but then I'd hear a modem tone, > wouldn't I? Incidentally, I get these calls both long-distance and local. > Anybody have any idea what's going on? Originating modems do not emit tones on connection. Terminating (or answering) modems answer the call with one of a variety of tones to indicate the type of modem and its desired speed of connection (300, 1200, 2400, or other). The clicking you hear in the earpiece is probably the modem switching its various filters in and out of circuit to determine what type of modem it is connected to. Try whistling a low, continuous tone into the mouthpiece (and varying the frequency you whistle) and see if you get the other end to start its transmission speed negotiation preamble (that will definitely identify the other end as a modem). I have used that trick to see if connections I was trying to debug were getting through to a modem, when I couldn't bridge a speaker or butt set onto the line. I don't design or work with modems other than as a user, so I may be wrong on the explanations of the clicking. I can speak from experience about the originating modems not generating tones, unless some of the newer, fancier modems that have come into use in the last few years do things differently. Don Ritchey dritchey@cbnewsc.att.com (or in real life) dritchey@ihlpb.att.com AT&T Bell Labs IH 1D-409 Naperville, IL 60566 (312) 979-6179
dplatt@coherent.com (Dave Platt) (09/23/89)
In article <telecom-v09i0393m03@vector.dallas.tx.us> you write: > > I moved a couple of months back, and I've had a weird problem since then. I > get lots of wrong numbers. Some of them are the normal "Is Joe there?" and > I say no and the person goes away. But the vast majority of them have no > voice at all. I pick up the phone, hear a faint 'clickclickclick' in the > background, and nothing happens, so I hang up. On my answering machine, > I don't get any message either; just those faint sounds. I thought perhaps > it was people calling me from a computer, but then I'd hear a modem tone, > wouldn't I? ... No, you would very probably not hear a modem tone, if a modem were dialing you. With most modems in use today, the _answering_ modem is responsible for sending the first tone, after it goes off-hook. The type of answer-tone transmitted identifies the protocol(s) that the answering modem is able to use. The originating modem "hears" the answer tone, chooses a protocol, and begins transmitting its carrier. The answering modem "hears" the originator's carrier, stops sending the answer-tone, and begins transmitting its carrier. If, on the other hand, the originating modem never "hears" an answer tone, it will never "know" that the call has been answered, and will simply disconnect after 30 seconds or a minute and report a "NO CARRIER" situation to its pilot. So, a local- or long-distance call with nothing but silence on the other end could very well be from a modem. There are a couple of relatively common ways that you can end up with numerous calls of this type: 1) Somebody at a specific computer site has misprogrammed one of their outdial modems... for example, transposing a digit in the phone-number used to contact one of their "neighbor" systems. If this has occurred, most of all of the calls you receive will be from the same exchange (either all local, or all long-distance), and there's a fairly good chance that they'll stop after a few weeks. The sysadmin of the offending system will (probably) notice that a large number of calls aren't getting through, will figure out the problem, and will correct his/her dialer-file. 2) The phone numbers for computer-hobbyist "bulletin board" systems tend to be passed around between personal-computer users. Bulletin-board systems tend to come and go fairly frequently... the survival time for a BBS tends to be measured in months. If the phone number for a BBS is circulated widely, then there may be literally thousands of people who have a copy of the number. If that BBS then goes out of service (for example, if its owner/sysop moves), then the phone number will often be given out to someone who is having phone service installed. Subsequently, the new "owner" of this number will receive many, MANY phone-calls from computer hobbyists who aren't aware that the BBS is out of service. I rather suspect that you're facing the second of these situations, since you seem to be receiving calls from both local and long-distance sources. The only really effective solution of which I'm aware is to ask the phone company to give you a different phone number. They'll probably charge you for the service-change, since they can legitimately argue that the problem is not _their_ fault. Dave Platt FIDONET: Dave Platt on 1:204/444 VOICE: (415) 493-8805 UUCP: ...!{ames,sun,uunet}!coherent!dplatt DOMAIN: dplatt@coherent.com INTERNET: coherent!dplatt@ames.arpa, ...@uunet.uu.net USNAIL: Coherent Thought Inc. 3350 West Bayshore #205 Palo Alto CA 94303 [Moderator's Note: Some telcos, like Illinois Bell, will change a subscriber's number once for free, if the subscriber complains of receiving nuisance or obscene calls. The original correspondent's complaint would probably fit in this category. PT]
rce10845@uxa.cso.uiuc.edu (Robert C Elliott) (09/23/89)
That is probably a modem calling you. The clicking sound is from the modem trying to determine if the phone is ringing, voice answer, or another modem. Only an answering modem puts out a tone right away; the originating modem responds only when it hears that tone. That's why you don't hear any modem tones. Rob Elliott: rce10845@uxa.cso.uiuc.edu (summer: rob@embossed.com)
dave@uunet.uu.net (Dave Levenson) (09/23/89)
In article <telecom-v09i0393m03@vector.dallas.tx.us>, well!slf@lll-crg.llnl. gov (Sharon Lynne Fisher) writes: ... > I thought perhaps it was people calling me from a computer, but > then I'd hear a modem tone, wouldn't I?... No, Sharon, a modem originating a call to another modem remains silent, and expects the answering modem to make a tone first. (Much like people ... the answering party generally speaks first.) Your calls may, in deed, be coming from a modem, or perhaps a fax machine. If it's convenient, you might wish to let your modem answer, and see if the calling person or device responds to its answer tone with a carrier. Dave Levenson Voice: (201) 647 0900 Westmark, Inc. Internet: dave@westmark.uu.net Warren, NJ, USA UUCP: {uunet | rutgers | att}!westmark!dave [The Man in the Mooney] AT&T Mail: !westmark!dave
john@zygot.ati.com (John Higdon) (09/23/89)
In article <telecom-v09i0393m03@vector.dallas.tx.us>, well!slf@lll-crg.llnl. gov (Sharon Lynne Fisher) writes: > I don't get any message either; just those faint sounds. I thought perhaps > it was people calling me from a computer, but then I'd hear a modem tone, > wouldn't I? Incidentally, I get these calls both long-distance and local. > Anybody have any idea what's going on? How do you know that they're long distance or local? Anyway, it could be a modem calling you (like a wrong number in someone's Systems file!) and you would hear nothing when you answered. Remember, an originating modem needs to hear the answering modem's tone before it will speak. If you have a modem, you might let it answer your phone for awhile and see if something connects with it:-) John Higdon | P. O. Box 7648 | +1 408 723 1395 john@zygot.ati.com | San Jose, CA 95150 | M o o !
rog@ucsd.edu (Roger Haaheim) (09/23/89)
Sounds like an autodialer listening for a "modem carrier"; when it doesn't get one, it hangs up and goes on to the next number.
sharon@asylum.sf.ca.us (Sharon Fisher) (09/25/89)
In article <telecom-v09i0399m07@vector.dallas.tx.us> john@zygot.ati.com (John Higdon) writes: >How do you know that they're long distance or local? Just a guess, really, but some of the calls sound real clear and some have those "seashell up to your ear" sounds that I associate with long distance calls. >Anyway, it could >be a modem calling you (like a wrong number in someone's Systems file!) >and you would hear nothing when you answered. Remember, an originating >modem needs to hear the answering modem's tone before it will speak. If >you have a modem, you might let it answer your phone for awhile and see >if something connects with it:-) Maybe next time I'm away for a weekend. I'd rather not do that during the week because I get many business calls and I'd hate to miss one. I've also gotten several postings by e-mail suggesting the same thing (plus one suggesting it might be a fax machine). Thanks... - Sharon Fischer -
len@csd4.csd.uwm.edu (Leonard P Levine) (09/27/89)
From article <telecom-v09i0406m04@vector.dallas.tx.us>, by sharon@asylum.sf. ca.us (Sharon Fisher): >>Anyway, it could >>be a modem calling you (like a wrong number in someone's Systems file!) >>and you would hear nothing when you answered. Remember, an originating >>modem needs to hear the answering modem's tone before it will speak. If >>you have a modem, you might let it answer your phone for awhile and see >>if something connects with it:-) I know that you can whistle a modem up. Try responding to this no voice caller with a swept frequency whistle. Often modems will "hook up" and then disconnect when you do it. A click, a bleep and a hangup will result. + - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - + | Leonard P. Levine e-mail len@evax.cs.uwm.edu | | Professor, Computer Science Office (414) 229-5170 | | University of Wisconsin-Milwaukee Home (414) 962-4719 | | Milwaukee, WI 53201 U.S.A. FAX (414) 229-6958 | + - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - +