Received: from buita.bu.edu by buit1.bu.edu (3.2/4.7) id AA03965; Tue, 26 May 87 23:12:56 EDT Return-Path: Received: by buita.bu.edu (1.1/4.7) id AA09893; Tue, 26 May 87 23:12:52 EDT Message-Id: <8705270312.AA09893@buita.bu.edu> Date: Tue, 26 May 87 23:12:39 EDT From: The Moderator (JSol) Reply-To: TELECOM@BUIT1.BU.EDU Subject: TELECOM Digest V7 #6 To: TELECOM@BUIT1.BU.EDU Status: RO TELECOM Digest Tue, 26 May 87 23:12:39 EDT Volume 7 : Issue 6 Today's Topics: Re: Submission for comp.dcom.telecom (Use of shielded cable for telepho Submission for comp-dcom-telecom Re: Extended phone services in California cellular inquiry ---------------------------------------------------------------------- To: comp-dcom-telecom@ucbvax.Berkeley.EDU From: hoptoad!pozar@ucbvax.Berkeley.EDU (Tim Pozar) Subject: Re: Submission for comp.dcom.telecom (Use of shielded cable for telephones) Date: 26 May 87 04:10:44 GMT In article <8705230318.AA03545@seismo.CSS.GOV> kitty!larry@SEISMO.CSS.GOV writes: >In a recent article dbj@RICE.EDU (Dave Johnson) writes: >> I need to wire a new phone line through a house for use with a modem. >> Is there some kind of sheilded phone cable that I could use to help >> reduce any noise in the connection? Anything else I should be aware >> of when routing the wire such as not getting too close to electrical >> wires? Thanks. > > I can think of no valid reason to use shielded telephone cable I can give you one reason: RFI or Radio Frequency Interference. I spec'ed a Northern Telecom SL-1 (s series) for our AM station in San Jose. I knew at that time there was some pretty nasty RF levels in the building and cofermed them with a RF field strength meter. 200volts per meter! The building contains a 50Kw transmitter and sits in the main lobe of the direc- tional. When we spec'ed the SL-1, I told Pac Tel (the folks we were purchasing the switch from) that they would be encountering some high RF and shielded, twisted pair would be advisable when installing the sets. They said, "No problem", and instaled unshielded, twisted pair. Boy did they lose money on our purchase! They had to not only reinstall shielded, twisted pair, but drop .01uf caps on all the lines and ferrite beads! Now I relize that most houseing will not be right next to a 50,000 watt AM radio station, but if you are one of the small unfortunate RFI can be handled with shielded wire and mabey a couple of .01uf caps. -- Tim Pozar UUCP pozar@hoptoad.UUCP Fido 125/406 USNail KLOK-FM 77 Maiden Lane San Francisco CA 94108 ------------------------------ To: comp-dcom-telecom@ucbvax.Berkeley.EDU From: hoptoad!pozar@ucbvax.Berkeley.EDU (Tim Pozar) Subject: Re: Submission for comp.dcom.telecom (Use of shielded cable for telephones) Date: 26 May 87 04:10:44 GMT In article <8705230318.AA03545@seismo.CSS.GOV> kitty!larry@SEISMO.CSS.GOV writes: >In a recent article dbj@RICE.EDU (Dave Johnson) writes: >> I need to wire a new phone line through a house for use with a modem. >> Is there some kind of sheilded phone cable that I could use to help >> reduce any noise in the connection? Anything else I should be aware >> of when routing the wire such as not getting too close to electrical >> wires? Thanks. > > I can think of no valid reason to use shielded telephone cable I can give you one reason: RFI or Radio Frequency Interference. I spec'ed a Northern Telecom SL-1 (s series) for our AM station in San Jose. I knew at that time there was some pretty nasty RF levels in the building and cofermed them with a RF field strength meter. 200volts per meter! The building contains a 50Kw transmitter and sits in the main lobe of the direc- tional. When we spec'ed the SL-1, I told Pac Tel (the folks we were purchasing the switch from) that they would be encountering some high RF and shielded, twisted pair would be advisable when installing the sets. They said, "No problem", and instaled unshielded, twisted pair. Boy did they lose money on our purchase! They had to not only reinstall shielded, twisted pair, but drop .01uf caps on all the lines and ferrite beads! Now I relize that most houseing will not be right next to a 50,000 watt AM radio station, but if you are one of the small unfortunate RFI can be handled with shielded wire and mabey a couple of .01uf caps. -- Tim Pozar UUCP pozar@hoptoad.UUCP Fido 125/406 USNail KLOK-FM 77 Maiden Lane San Francisco CA 94108 From: root@sgi.sgi.com (Superuser) Date: 26 May 87 09:02:30 GMT To: ames!comp-dcom-telecom@ames Subject: Submission for comp-dcom-telecom Path: sgi!wdl1!kck From: kck@wdl1.UUCP (Karl C. Kelley) Newsgroups: comp.dcom.telecom Subject: Re: Extended phone services in California Message-ID: <3590001@wdl1.UUCP> Date: 26 May 87 07:43:00 GMT References: <8705221624.AA07193@blia.BLI> Lines: 11 few weeks ago I got a note from my telephone co (pacbell) informing that they are going to install some kind of new equipment and telling me that if I use things like a modem (which i'm using now) or an answering machine, (which i have come to depend on a great deal), that I should contact the place where I bought the equipment and THEY would be able to tell me if any adjustment is needed when this new telco equipment comes online. This irritates me because I have little hope of going to the electronics dept at Emporium and getting a rational response to my query. It strikes me that I might have better luck asking the question here, since some of you appear to follow these things, and in particular this entry looks like it could be related. Anybody out there know if these two things are related, or what the phone co has in mind? ------------------------------ To: comp-dcom-telecom@ucbvax.Berkeley.EDU From: hoptoad!pozar@ucbvax.Berkeley.EDU (Tim Pozar) Subject: Re: Submission for comp.dcom.telecom (Use of shielded cable for telephones) Date: 26 May 87 04:10:44 GMT In article <8705230318.AA03545@seismo.CSS.GOV> kitty!larry@SEISMO.CSS.GOV writes: >In a recent article dbj@RICE.EDU (Dave Johnson) writes: >> I need to wire a new phone line through a house for use with a modem. >> Is there some kind of sheilded phone cable that I could use to help >> reduce any noise in the connection? Anything else I should be aware >> of when routing the wire such as not getting too close to electrical >> wires? Thanks. > > I can think of no valid reason to use shielded telephone cable I can give you one reason: RFI or Radio Frequency Interference. I spec'ed a Northern Telecom SL-1 (s series) for our AM station in San Jose. I knew at that time there was some pretty nasty RF levels in the building and cofermed them with a RF field strength meter. 200volts per meter! The building contains a 50Kw transmitter and sits in the main lobe of the direc- tional. When we spec'ed the SL-1, I told Pac Tel (the folks we were purchasing the switch from) that they would be encountering some high RF and shielded, twisted pair would be advisable when installing the sets. They said, "No problem", and instaled unshielded, twisted pair. Boy did they lose money on our purchase! They had to not only reinstall shielded, twisted pair, but drop .01uf caps on all the lines and ferrite beads! Now I relize that most houseing will not be right next to a 50,000 watt AM radio station, but if you are one of the small unfortunate RFI can be handled with shielded wire and mabey a couple of .01uf caps. -- Tim Pozar UUCP pozar@hoptoad.UUCP Fido 125/406 USNail KLOK-FM 77 Maiden Lane San Francisco CA 94108 From: root@sgi.sgi.com (Superuser) Date: 26 May 87 09:02:30 GMT To: ames!comp-dcom-telecom@ames Subject: Submission for comp-dcom-telecom Path: sgi!wdl1!kck From: kck@wdl1.UUCP (Karl C. Kelley) Newsgroups: comp.dcom.telecom Subject: Re: Extended phone services in California Message-ID: <3590001@wdl1.UUCP> Date: 26 May 87 07:43:00 GMT References: <8705221624.AA07193@blia.BLI> Lines: 11 few weeks ago I got a note from my telephone co (pacbell) informing that they are going to install some kind of new equipment and telling me that if I use things like a modem (which i'm using now) or an answering machine, (which i have come to depend on a great deal), that I should contact the place where I bought the equipment and THEY would be able to tell me if any adjustment is needed when this new telco equipment comes online. This irritates me because I have little hope of going to the electronics dept at Emporium and getting a rational response to my query. It strikes me that I might have better luck asking the question here, since some of you appear to follow these things, and in particular this entry looks like it could be related. Anybody out there know if these two things are related, or what the phone co has in mind? Date: Tue, 19 May 87 06:32:11 mdt From: utah-cs!gr.utah.edu!uplherc!wicat!uucp@seismo.CSS.GOV (UUCP) To: comp-dcom-telecom@seismo.CSS.GOV ------------------------------ To: comp-dcom-telecom@ucbvax.Berkeley.EDU From: hoptoad!pozar@ucbvax.Berkeley.EDU (Tim Pozar) Subject: Re: Submission for comp.dcom.telecom (Use of shielded cable for telephones) Date: 26 May 87 04:10:44 GMT In article <8705230318.AA03545@seismo.CSS.GOV> kitty!larry@SEISMO.CSS.GOV writes: >In a recent article dbj@RICE.EDU (Dave Johnson) writes: >> I need to wire a new phone line through a house for use with a modem. >> Is there some kind of sheilded phone cable that I could use to help >> reduce any noise in the connection? Anything else I should be aware >> of when routing the wire such as not getting too close to electrical >> wires? Thanks. > > I can think of no valid reason to use shielded telephone cable I can give you one reason: RFI or Radio Frequency Interference. I spec'ed a Northern Telecom SL-1 (s series) for our AM station in San Jose. I knew at that time there was some pretty nasty RF levels in the building and cofermed them with a RF field strength meter. 200volts per meter! The building contains a 50Kw transmitter and sits in the main lobe of the direc- tional. When we spec'ed the SL-1, I told Pac Tel (the folks we were purchasing the switch from) that they would be encountering some high RF and shielded, twisted pair would be advisable when installing the sets. They said, "No problem", and instaled unshielded, twisted pair. Boy did they lose money on our purchase! They had to not only reinstall shielded, twisted pair, but drop .01uf caps on all the lines and ferrite beads! Now I relize that most houseing will not be right next to a 50,000 watt AM radio station, but if you are one of the small unfortunate RFI can be handled with shielded wire and mabey a couple of .01uf caps. -- Tim Pozar UUCP pozar@hoptoad.UUCP Fido 125/406 USNail KLOK-FM 77 Maiden Lane San Francisco CA 94108 From: root@sgi.sgi.com (Superuser) Date: 26 May 87 09:02:30 GMT To: ames!comp-dcom-telecom@ames Subject: Submission for comp-dcom-telecom Path: sgi!wdl1!kck From: kck@wdl1.UUCP (Karl C. Kelley) Newsgroups: comp.dcom.telecom Subject: Re: Extended phone services in California Message-ID: <3590001@wdl1.UUCP> Date: 26 May 87 07:43:00 GMT References: <8705221624.AA07193@blia.BLI> Lines: 11 few weeks ago I got a note from my telephone co (pacbell) informing that they are going to install some kind of new equipment and telling me that if I use things like a modem (which i'm using now) or an answering machine, (which i have come to depend on a great deal), that I should contact the place where I bought the equipment and THEY would be able to tell me if any adjustment is needed when this new telco equipment comes online. This irritates me because I have little hope of going to the electronics dept at Emporium and getting a rational response to my query. It strikes me that I might have better luck asking the question here, since some of you appear to follow these things, and in particular this entry looks like it could be related. Anybody out there know if these two things are related, or what the phone co has in mind? Date: Tue, 19 May 87 06:32:11 mdt From: utah-cs!gr.utah.edu!uplherc!wicat!uucp@seismo.CSS.GOV (UUCP) To: comp-dcom-telecom@seismo.CSS.GOV From: SPGDCM%UCBCMSA.Berkeley.EDU@berkeley.edu Date: Tue, 26 May 87 17:36:45 PDT To: telecom@buit1.bu.edu Subject: cellular inquiry MSG:FROM: SPGDCM --UCBCMSA TO: NETWORK --NETWORK 05/26/87 17:36:44 To: NETWORK --NETWORK Network Address From: Doug Mosher Title: MVS/Tandem Systems Manager (415)642-5823 Office: Evans 257, Univ. of California, Berkeley, CA 94720 Subject: cellular inquiry To: telecom@buit1.bu.edu I do not yet understand enough about the cellular technology, and perhaps the answers are relatively simple and of interest to others as well as me. (If not, the moderator may wish to divert the discussion). Clearly a customer can rent a cellular phone, and register for service in a particular area; then they can both send and receive calls. The technology somehow recognizes and notes the user's location as they drive about, and knows in what cell to ring them if an outsider calls them. The questions: 1. How is the location-recognition accomplished? Does one's currently inactive cellular phone burp regularly and its address get re-noted? Does that drain your battery? If it's really off are callers told something different from "ring...ring...ring...no answer"? 2. Over how large an area does this typically work? 3. If an owner drives from SF, normal location, to New York, and tries to call out, what happens? 4. If while they are in New York, someone in SF, their home, calls them, what happens? 5. Can you register as a visitor in a distant area, electronically or by calling in or however? Does this enable anyone else to call you from long distance? Must they know, essentially, where you went and when you're there? Thanks, Doug [ cellular inquiry ------------------------------ End of TELECOM Digest *********************