648 lines
31 KiB
Plaintext
648 lines
31 KiB
Plaintext
From telecom@delta.eecs.nwu.edu Sun Feb 9 03:11:51 1992
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Received: from delta.eecs.nwu.edu by gaak.LCS.MIT.EDU via TCP with SMTP
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id AA01693; Sun, 9 Feb 92 03:11:43 EST
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Received: by delta.eecs.nwu.edu id AA15363
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(5.65c/IDA-1.4.4 for ptownson@gaak.lcs.mit.edu); Sun, 9 Feb 1992 02:11:34 -0600
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Date: Sun, 9 Feb 1992 02:11:34 -0600
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From: TELECOM Moderator <telecom@delta.eecs.nwu.edu>
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Message-Id: <199202090811.AA15363@delta.eecs.nwu.edu>
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To: ptownson@gaak.LCS.MIT.EDU
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Subject: computer to hotel phone
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Status: R
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From telecom Thu Feb 6 16:44:45 1992
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Date: Thu, 6 Feb 92 10:50:17 -0800
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From: Jeff Sicherman <sichermn@beach.csulb.edu>
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Subject: Re: Are Acoustic Couplers Still Around?
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20 July 1990
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IMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM;
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: :
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: HOW TO CONNECT YOUR COMPUTER TO A HOTEL PHONE :
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: :
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HMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM<
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By Paul Mu$oz-Colman [71141,1224]
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Earle Robinson [76004,1762]
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Charles Wangersky [73747,2656]
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Connie Kageyama [76703,1010]
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John Boyd [75076,2466]
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Robin Garr [76702,764]
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Updated from an idea originally written by
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Joan Friedman [76556,3643]
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------------
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INTRODUCTION
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------------
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This file describes a method which you can use, and equipment which you can buy
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to use your computer and its modem with phone systems which aren't familiar to
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you. Telephone systems are very different in appearance and design. There are
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wall phones, desk phones, and cordless phones. (For your purposes, with
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cordless phones, you deal only with the base station set, not the movable
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part.)
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There are hard-wired phone lines, all sorts of national phone plugs and jacks,
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and modular (small plastic connector) plugs and jacks.
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A few simple facts are all you need to make it easy to connect your computer
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and become productive.
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-------------
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BASIC CONCEPT
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-------------
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The idea of connecting a telephone in a strange location to your computer is as
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simple as it is at home. The basic principal is to connect the modem's LINE
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jack to the hotel phone's incoming phone line--the wires that feed the
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connection to the hotel's instrument.
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Most telephone systems have one thing in common: no matter how many wires
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connect the telephone to the outside, only TWO are used for the "talk pair", or
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what gives you the ability to connect the computer. This concept is very
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important: your mission is to determine how to connect to this pair of wires
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and stay AWAY from all of the rest of them!
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--------------------------------
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ELECTRONIC SAFETY MUST BE FIRST!
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--------------------------------
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First, a little defensive measure! The wires which you use to connect your
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modem to the telephone system must have ONLY TWO copper conductors in them. You
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can visit Radio Shack (known as Tandy in Europe), or your computer supplier,
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and obtain a modular telephone cord like this which has a plug on each end. If
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you look at the plug very carefully, you'll notice that it has six little
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grooves, on the side of the plug opposite the tab which you press to unplug it.
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Some of these grooves are shiny, and some look like plain plastic. The ones
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which are shiny have conductors (metal that connects the groove [or pin, as
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it's called] to the same groove on the other end). If you hold the cord up to
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the light, and if it has a translucent outer cover, you can see two wires
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running through the length of it. You will also be able to see the wires in
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each of the two plugs, since the plugs are made out of clear plastic. In some
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of the cords, if you look closely, you'll see that the center two wires are
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colored red and green.
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Common home telephone cords have four conductors out of the six grooves; you
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only want the MIDDLE TWO to be connected.
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Why be defensive? Strange telephone systems may use the other pins for
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various purposes, such as signalling a message waiting for you at the hotel
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desk. Some computer modems have the conductors other than the talk pair
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connected to the phone jack, as well, and strange phone systems can destroy
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your modem if the wrong electrical signals appear.
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Not only are we worried about only having the talk pair connected to your
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modem, we have to worry about stray electrical currents through the phone line
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itself, such as the jolts from lightning (which can wipe you RIGHT out)! You
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need to have a telephone line surge suppressor that you plug into the hotel's
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phone outlet, and your modem's cord into the suppressor. Note that most phone
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line surge suppressors also will have to plug into your power strip; the way
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the suppressor works, it takes the surge that is coming up the wires to
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explode your modem, and instead convinces it to go down the ground wire of
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your power strip, where there is nothing that can get hurt by it. This, in
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case you hadn't noticed, is a Good Thing.
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-------------------------
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AHA! A PICTURE, AT LAST!
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-------------------------
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Now, the connection idea. Here is a simple drawing of what we're trying to
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achieve. The idea is to connect your computer to its modem (unless you have a
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portable which has it connected internally). If it is external, you then
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connect the computer's and the modem's electrical cords to your power strip,
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which MUST contain an AC power surge suppressor (not the same as the phone
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suppressor). If you are in a country whose electrical supply is 220 volts,
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you will need to get a 220V power strip with surge suppressor; 110V surge
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suppressors have been known to literally explode when connected to a 220V
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power line, and even when connected to the 110-volt end of a 220V to 110V
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transformer.
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In portables, these two
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are generally in the
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same casing your phone surge suppressor
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/ \ /
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IMMMMMMMMMM; IMMMMMMMMMM; ZD? IMMMMMMMMMM;
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: your GDDDDDDD6 your G--------4 C----6 hotel's :
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: computer : RS232 : modem : phone @BY : phone or :
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HMMMMKMMMMM< HMMMMKMMMMM< line 3 : line :
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: : 3 HMMMMMMMMMM<
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ZDDDDDDDPDDDDDDDDDDDDDDDDDDPDDDDDDDDDDDDDDDADDDD?
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3 your AC power strip which is surge-suppressed 3
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@DDDDDDDDDDDDDDDDDDDDDDDRDDDDDDDDDDDDDDDDDDDDDDDY
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IMMMMMMMMMMMMMJMMMMMMMMMMMMM;
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: hotel's electrical outlet :
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HMMMMMMMMMMMMMMMMMMMMMMMMMMM<
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-------------------------------------------
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AC POWER 1: CONNECTING WITH A CONVERTER KIT
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-------------------------------------------
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You are, of course, travelling with your AC power bar and surge suppressor.
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You should also have a power line polarity checker (polarity means which way
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two wires connect to where they're going [there are only two choices,
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right?]). If your modem is internal, you have one electrical cord to connect;
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if external, you'll have two; many phone line surge suppressors use the ground
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pin on a third, so you would have to connect that as well. You should also
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have an extension cord in case the hotel's outlet is not convenient to either
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you or the phone line; this should probably be the 110-volt variety. The
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adapter plugs that come with most converter kits, and the transformers sold in
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most converter kits, are *not* grounded; you may have to run a separate wire
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from the center screw in the wall outlet in the hotel room, to the wire
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attached to your 2-prong to 3-prong adapter. Most foreign power kits come
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with two 220V to 110V boxes, a little light one, rated at 1000 watts or more,
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called a "Converter", and a heavy one about the same size, rated 50 watts and
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called a "Transformer". DO NOT, under any circumstances, plug your computer
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or modem into the 1000-watt converter; if you do, you will suddenly have a
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room full of smoke and no computer any more.
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To hook yourself up to the power line, then, you should do the following:
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1) Connect the wire on the 110V 2-prong to 3-prong converter to the screw in
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the center of the power outlet. We do this first because it will be harder
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to reach this screw after something has been plugged in.
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2) If in a location where the use of a transformer is appropriate, plug the
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transformer into the wall, with the appropriate connectors.
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3) Plug the 2-prong to 3-prong adapter into the converter.
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4) Plug the power-line polarity checker into the 2-prong to 3-prong adapter.
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If it indicates that the polarity is reversed, unplug the transformer from
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the adapter plug, turn it around, and plug it back in.
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NOTE: If the polarity checker still says you have reversed polarity, you
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are going to have to attach to the phone and power lines without surge
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suppression; you might want to send a brief prayer to the patron saint of
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communications. Then, disconnect the wire from the center screw of the
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power outlet.
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5) Unplug the line polarity checker, and plug the power bar or surge
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suppressor into the 110V outlet at the end of the whole business.
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-------------------------------------------
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AC POWER 2: CONNECTING DIRECTLY TO THE WALL
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-------------------------------------------
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If your modem or computer is rated for the voltage available where you are
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located (220 to 240 volts for 220-volt equipment or 110 to 130 volts for
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110-volt equipment), you can plug it directly into the hotel's outlet. If in
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a 220 to 240-volt area, you will need to get a 240-volt surge suppressor,
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preferably in the country where you are travelling; then, plug that into the
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wall, and plug your grounded 240V power-strip into that. Most European
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countries use a round plug with two round prongs and a metal strip up the side
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for ground; the UK is rather vastly different, with a square 3-prong plug.
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So, unless your travels are going to cross the UK, you should be all right
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with a single type of power bar and surge suppressor.
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We have never seen a phone-line surge suppressor in Europe; no doubt they will
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be following hot on the heels of deregulation, but for the moment, you have to
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put your trust in the PTT.
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--------------------------------
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AC POWER 3: WHAT USUALLY HAPPENS
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--------------------------------
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Usually, a 220-volt-equipped computer takes too much power for the little
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50-watt transformer; or, the computer plus the modem sum to more than 50
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watts, but the computer's battery charger draws less than 50 watts. What you
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do then is run the computer off 220V, or off its internal batteries; and the
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modem off the transformer. You will still need to connect the power strip, or
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the surge suppressor, as mentioned in AC Power 1, in order to get the phone
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line surge suppressor to work.
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------------------------------
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DIFFERENT TYPES OF PHONE CORDS
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------------------------------
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Not only should you obtain a modular telephone cord with only two conductors
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in it, but you should also obtain one with a modular plug on one end, and what
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are called "spade lugs" on the other (metal U-shaped connectors which can slip
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under the head of a screw, which is then tightened down to make an electrical
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contact of metal to metal).
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---------------
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RJ-14 THREE-TAP
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---------------
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At Tandy/Radio Shack, you can buy what's called an RJ-14 three-tap connector.
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One end of this plugs into a modular phone jack which can be either one-line
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or two-line capable. The other end has an identical RJ-14 outlet, and two
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other RJ-11 outlets, one stenciled with LINE 1, and the other with LINE 2.
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(VERY IMPORTANT: You aren't going to use LINE 2 at all for this purpose.)
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-------------------------------------------------
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MODULAR, RJ-11, RJ-14: WHAT DOES THIS STUFF MEAN?
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-------------------------------------------------
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Well, it's like this. Before the "breakup", Ma Bell (actually Western
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Electric) invented this new, neat system to connect phones to the wall, and to
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connect phones together; you can replace bits of the phone that are most
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likely to break, namely the wires, without having to open the case of the
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phone. Just plug in a new wire.
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Because you can repair a phone simply by replacing the specific modules that
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make it up, the whole system became known as "modular connectors". These come
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in a number of sizes: two, four, six, up to twelve connectors; and they are
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extremely rugged, as anything attached to a telephone is, so a lot of other
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people started using them for things totally unconnected with the phone
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company. Many manufacturers now use a modular jack to connect the keyboard to
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its PPC series of computer.
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However, the electronics industry couldn't be satisfied with just calling it
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"modular"; they have a different name for each type of hookup. The name, as
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is typical of such interface standards, is a series of letters and numbers.
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The three types that we will be most interested in are the RJ-11, RJ-12, and
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RJ-14.
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Most home lines, and most modems, are connected to RJ-11 phone lines. This is
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a six-connector jack, with only two pins actually used.
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An RJ-12 connector is the exact same size and shape, except that it has four
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wires used instead of two. The two extra wires are used by some phone systems
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to indicate that a line is in use. You don't have to worry about that; your
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modem won't.
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An RJ-14 connector uses four wires also, but instead of using the extra two
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wires to signal that a line is in use, it uses them to put a second phone line
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on the same cable. The center two wires are the main phone line, and the outer
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two are the second. (Actually, many US home phone systems are equipped with
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RJ-14 modular cords even though the hookup is RJ-11 (two wires), just in case
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you decide to add a second line, making hookup easier for the installer. The
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center two wires are the main or first phone line, and the next outer two are
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the second.)
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--------------------
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NATIONAL PHONE PLUGS
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--------------------
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In every country, the national standard for the phone plug is different; so,
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you will need to stop by an electronics parts store to buy a PTT-to-RJ-11
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adapter in each country you visit. Normally, this adapter plug will be the
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local currency equivalent of $3 to $10. In most countries, you can find this
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adapter in virtually any electronics parts store.
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In London, most of the electronics parts stores cluster in the Tottenham Court
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Road.
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In Paris, the place to look is the BHV.
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In Den Haag (the Hague) in the Netherlands, there are a number of stores
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around the Pavilioensgracht, though the best store we've found is Stuurt en
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Bruin at Prinsegracht 34. You can also buy the adapter plug at any Primafoon
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outlet in the Netherlands; addresses for Primafoon will be in the very
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beginning of the white pages section of the phone book. (Look for a page
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printed in green.)
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And, nowadays, in the U.S., most hotels and motels use the modular connector
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almost exclusively.
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--------------------------
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OLD-STYLE FOUR-PRONG PLUGS
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--------------------------
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You may also need a special converter which has a modular phone jack on one
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end and a four-prong phone plug on the other; Radio Shack has these.
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-----------
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OTHER TOOLS
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-----------
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Last in your kit, have a flat-blade screwdriver (1/4 inch is required, and 1/8
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inch is convenient), and a phillips screwdriver (#1 is the most common size).
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--------------------------
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MOVING RIGHT ALONG, NOW!
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--------------------------
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------------------------
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PHONES WITH MODEM JACKS!
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------------------------
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Nirvana! The easiest hookup is going to be in the very modern hotels, which
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have telephones that contain a modem plug; when you encounter this, you laugh
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a lot, first! Plug your two-conductor modular cord into the phone jack, and
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the other end into modem, just as if you were at home! Put me away, you need
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read no more! Dial CompuServe and get your latest stock quotes!
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------------------------------
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PHONES WITH MODULAR WALL JACKS
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------------------------------
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The next best hookup is a hotel where the telephone is connected to the wall
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with a modular plug. (Sometimes the modular plug is hidden behind a wall
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plate that you must unscrew first.) When you unclip the modular plug from the
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wall, plug your RJ-14 3-splitter into the wall. Plug the HOTEL's phone back
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into the tap marked RJ-14. Plug YOUR two-conductor modular cord into the tap
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marked LINE 1, and again, read no farther!
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-------------------------------
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PHONES WITH FOUR-PRONG PLUGS
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-------------------------------
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If you find a phone with an old-style four-prong plug, unplug the phone, plug
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in your modular-to-four-prong converter, plug your modular extension cord into
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the wall, and go to it!
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--------------------------
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PHONES WITH NATIONAL PLUGS
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--------------------------
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If you find a phone with a national plug, unplug the phone, plug in your
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PTT-to-RJ-11 converter, plug your modular extension cord into the concverter,
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and go to it!
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----------------------------------
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PHONES WITH A SQUARE CONNECTOR BOX
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----------------------------------
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Now it gets a little more difficult. You walk in and find a phone with a cord
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that goes into a little square box at the base of the wall. There are two
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kinds of these boxes, the kind with only a single screw in the cover, and the
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kind with no screws at all.
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If the box has a single screw in the center, take your 1/4 inch flat-blade
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screwdriver, and gently unscrew the screw.
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If there are no screws on the box at all, look around the top and sides of the
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box for a little slot, the right size to take your 1/4 inch screwdriver; when
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you find it, insert the screwdriver and gently twist it. The box will pop
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open on a hinge. (Note: this type of phone box is used especially in new
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construction in Canada.)
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You'll usually see three or four screws below the cover. Each screw will have
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one or more wires secured under it. The wires attached to the screws are
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usually color-coded, though the colors will be different for each country.
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In a lot of countries, they will have letter codes; two of the wires will be
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labelled something similar, like L1 and L2, or A and B, or if you are really
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lucky, "Tip" and "Ring".
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If there are lots of wires behind the wall plate, like 25 or 50, there will
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probably be also a lot of wires labelled the same way, "L1" and "L2", for
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instance. In this case, look only at the wires which are also connected to
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your phone. The other ones will be connected to other telephones in the hotel,
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and if you start playing with them, the hotel will be very mad at you.
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Carefully loosen one screw slightly, touching *only* that screw with your
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hands and the screw driver (if you touch the two screws that go to your phone
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at the same time and the phone happens to ring, you'll get a truly unpleasant
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jolt). Take your modular cord with the spade lugs, and slip one spade lug
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under it (don't let any other spade lugs slip out), and gently tighten the
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screw back down. Repeat the process for the other screw.
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If the screws are close together, be SURE not to let the metal from one spade
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lug TOUCH the metal from the other one!
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Crank up and compute!
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------------------------------------------------------
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PHONES THAT CAN'T BE OPENED OR WITH INACCESSIBLE WIRES
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------------------------------------------------------
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There's an alternative connecting device which can be obtained which will
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hook up phones where the *only* thing you can get to is the modular cord which
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clips into the mouthpiece. This isn't cheap, however, because of the
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electronics which are required to make this connection safely and correctly.
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See the description of the Konexx unit at the end of this kit.
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---------------------------------------------------------
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PHONES WITH DISAPPEARING WIRES AND WALL PHONES (ARGGHHH!)
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---------------------------------------------------------
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If you are lucky to find a wall phone that is plugged into a modular plate,
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you can push up FIRMLY on the bottom of the phone, which will move it up about
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half an inch (don't be surprised if you hear a snap when this happens), and
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remove it from the wall; plug in your modular cord (if you want to use the
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phone ALSO, don't remove it, just tap into it as follows).
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Sigh!
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All the easy solutions are gone now, but have no fear ... we'll get there. You
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find no modular or national plugs, and no little box in the wall ... the wire
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just disappears in there. So we tackle the telephone instead, to find those
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little two wires.
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Turn the phone over and find the screws which undo the case. If you have a
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conventional desk set, the screws are on the bottom. If you have a wall
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phone, the screws are under the "number card" plastic protector (you can pop
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this out with your 1/8 inch screwdriver blade). Take the case off the phone.
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Find the place where the phone wires connect to the phone line. In some
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countries, notably the Netherlands, this is under a plate on the bottom of the
|
|
phone which is held on by only one screw; this is all neatly labelled as well.
|
|
|
|
Follow the two wires you are looking for to the screws that hold them down.
|
|
Very often, this place appears on a plastic-looking wire block with many
|
|
screws. The two you need generally have something like "L1" and "L2" or "a"
|
|
and "b" stenciled next to the screws with the correct wires. DON'T touch any
|
|
other wires on this block!
|
|
|
|
Perform the process where you loosen the screw and hook your spade lugs into
|
|
them, and tighten down, one at a time.
|
|
|
|
Finally, take a break, relax, read the paper, take a swim, and compute at your
|
|
leisure ... YOU EARNED IT!
|
|
|
|
|
|
-------------------------------
|
|
COLOR CODING: HOW'S THAT AGAIN?
|
|
-------------------------------
|
|
|
|
Every country has its own standards for coding the telephone lines; these
|
|
usually depend on the colors of the wires, which means that you can't work
|
|
for the phone company if you are color blind...
|
|
|
|
For historical reasons, the two wires that make up your phone connection are
|
|
called "tip" and "ring". In the old days of the manual switchboard, each
|
|
phone line was connected to a single plug at the switchboard, which looked
|
|
very much like a large (1/4") stereo headphones plug. One line, the line that
|
|
was at the lower (and therefore safer to touch) voltage, was connected to the
|
|
connector at the tip of this plug, the other was connected to the ring around
|
|
the end of it, and the sleeve, or the rest of the plug, was connected to
|
|
ground.
|
|
|
|
In the United States and Canada, the tip connection is always on the green
|
|
wire, the ring was always red. Sleeve was yellow, for some reason, but that
|
|
wire was usually not connected, so the name "sleeve" for that wire didn't
|
|
become popular.
|
|
|
|
These days, the polarity of the phone wire doesn't matter as much; as recently
|
|
as 1980, a phone line had one polarity if it was a dial line, another if it
|
|
was a touch-tone line. Before the introduction of touch-tones, all phone lines
|
|
were supposed to have the same polarity. So many places will have tip and ring
|
|
reversed. To the best of our knowledge, no modem sold for personal cares
|
|
about whether tip and ring were reversed.
|
|
|
|
Every country has its own color coding for the wires, as we said earlier; the
|
|
following table, while still incomplete, will list the colors used for the
|
|
two wires that your modem *must* have in order to work. Where two colors are
|
|
listed in one column, this means that the main color of the wire is the first
|
|
color, and it has a stripe of the second color; so "blue-white" is a blue
|
|
wire with a white stripe. If you discover errors in the table, or want to
|
|
add a new country to the list, please post a message for SysOp in IBMCOM, or
|
|
in IBMEUR, or contact Charles Wangersky [73747,2656].
|
|
|
|
For what it's worth, if you wish, you can use a voltmeter instead of a line
|
|
tester. Some people (like us) travel with a voltmeter. In this case, you can
|
|
tell tip and ring on your phone line by checking for a 48-volt signal when the
|
|
phone is hung up or disconnected; the ring line will be at -48 volts from the
|
|
tip line. The tip line will be near ground potential; the way to tell the
|
|
difference between that and sleeve is to pick up the phone. The sleeve voltage
|
|
won't change, but the voltage on the tip line will go from about 0 to about -2
|
|
volts; meanwhile the voltage on the ring line will drop to about -10 volts.
|
|
|
|
|
|
Country 3 Tip (+) 3 Ring (-)
|
|
DDDDDDDDDDDDDDDDDDDDDEDDDDDDDDDDDDDEDDDDDDDDDDDDD
|
|
USA/Canada (normal) 3 Green 3 Red
|
|
USA/Canada (special) 3 Blue-White 3 White-Blue
|
|
Netherlands 3 Red 3 Blue
|
|
Germany 3 Red-black 3 Red
|
|
United Kingdom 3 White 3 Blue
|
|
|
|
|
|
----------------------------------------------------------
|
|
SPECIAL NOTE FOR PEOPLE TRAVELLING IN THE UK AND HONG KONG
|
|
----------------------------------------------------------
|
|
|
|
The United Kingdom and Hong Kong use a different make/break ratio in their
|
|
phone dialers; a dial pulse in the UK is 33% of the time between one pulse
|
|
and the next, where in the US it is 39%. This doesn't sound like a big
|
|
difference, but it is; if you try to use the US pulse ratio on a UK phone
|
|
line, it will not work.
|
|
|
|
Luckily, the people at Hayes who invented the standard for personal
|
|
direct-connect modems were aware of this difference, and so, starting with the
|
|
Smartmodem 1200 internal, included a command to change the make-break ratio;
|
|
and so nearly all other modems today have the ability to change from one to
|
|
the other. The command to set the UK pulse ratio is &P1; to reset it to US
|
|
standard, &P0.
|
|
|
|
So, to change to the UK standard, you could send the command "AT&P1&W" to your
|
|
modem; this will change its power up default to the UK system.
|
|
|
|
|
|
----------------------------------------------------
|
|
YOU MUST HEED THIS WARNING FOR YOUR OWN PROTECTION!!
|
|
----------------------------------------------------
|
|
|
|
Under no circumstances use ANY other wires inside the phone instrument or the
|
|
wall connector to connect to your modem. If you do so, you can destroy the
|
|
electronics inside the modem, inside the phone, and in some bizarre cases,
|
|
even inside your computer.
|
|
|
|
ONLY the L1 and L2 incoming wires have the proper electrical signals to give
|
|
to your modem's telephone line (the right combination of voltage, current,
|
|
signals, and other characteristics)! Under no circumstances use a connection
|
|
cord to your modem which has more than TWO conductors in it!
|
|
|
|
If the phone rings while you are connecting wires to it, or if you are
|
|
connecting wires while the phone is picked up, IT CAN BITE YOU! The voltage
|
|
used to ring the bells in the phone is 150 volts, 25 Hz; in the UK, it's 250V
|
|
at 25 Hz. This HURTS! If you have a weak heart, it can kill you! In many
|
|
countries, there is a meter on the phone; to make the meter tick over, the
|
|
phone company puts a pretty stiff voltage down the same wires that you will be
|
|
connecting to; in the Netherlands, this is 100 volts at 25 Hz. This also
|
|
hurts. When working with live circuits, remember this rule: ONLY ONE HAND ON
|
|
ANY PIECE OF EXPOSED METAL OF ANY KIND! EVER!
|
|
|
|
|
|
-------------------
|
|
YOUR PHONE KIT LIST
|
|
-------------------
|
|
|
|
All of this, except for the surge suppressor and the mouthpiece interface, can
|
|
be acquired for about $50 at Tandy/Radio Shack or a local hardware store.
|
|
The phone line surge suppressor is a Networx Wire Cube, and can be had for
|
|
about $30.
|
|
|
|
The kit should contain the following:
|
|
|
|
2 TWO-conductor modular-to-modular phone cords, each 25 feet long
|
|
If you can't find 25-foot long two-conductor cords, you
|
|
must have at LEAST one TWO-conductor cord of ANY length
|
|
used (you can combine this with FOUR-conductor cords with
|
|
your in-line connector).
|
|
1 in-line modular phone connector (hard plastic about 2" long)
|
|
1 3-jack RJ-14 to RJ-14 / RJ-11 / RJ-11 modular phone converter
|
|
1 TWO-conductor phone cord with modular connector on one end,
|
|
and two spade lug connectors on the other. If you can't find
|
|
a TWO conductor cord, buy a four conductor cord, and CUT the
|
|
spade lugs off of the yellow and black wires and throw them
|
|
away!
|
|
1/8" flat-blade screwdriver
|
|
1/4" flat-blade screwdriver
|
|
#1 phillips screwdriver
|
|
2-prong with strap to 3-prong electric plug tap
|
|
Power-line adapter kit
|
|
Power-line surge suppressor (either separate or built into power bar)
|
|
Power-line polarity checker
|
|
Heavy-duty three-prong electrical extension cord
|
|
Utility knife
|
|
|
|
--------------------------------------
|
|
OPTIONAL EXTRA ITEMS FOR THE PHONE KIT
|
|
--------------------------------------
|
|
|
|
One of the most useful things that you can get is the little AT&T or Radio
|
|
Shack phone line tester; this will plug into the RJ-11 jack and tell you
|
|
whether you've gotten it wired correctly. It can also detect whether you have
|
|
a single- or dual-line phone, if you find a modular jack already installed.
|
|
This gizmo is only available in North America; since modular jacks aren't very
|
|
popular as yet in Europe, the Tandy stores over here don't see any point in
|
|
carrying them. If you're already in Europe, and you need such a tester,
|
|
contact Earle Robinson [76004,1762]; he has kindly offered to provide these at
|
|
his cost to the first dozen (or so, depending on how many he picks up) people
|
|
who contact him after each of his trips to the States.
|
|
|
|
The mouthpiece interface is a Konexx unit, from Unlimited Systems Corp, Inc,
|
|
9225 Chesapeake Drive, Suite J, San Diego, CA 92123. Two models are
|
|
available. The 106 will work for most modems ($99), and the 107 ($125) will
|
|
support the few modems that require it and fax machines. The unit is about
|
|
2" x 1" x 1", and plugs into the telephone base unit where the hand set cord
|
|
goes. The hand set then plugs into one end of the unit, and your modem into
|
|
the other end. A switch changes from Voice to Data transmission.
|
|
|
|
|
|
---------------------------------
|
|
A WORD OF CAUTION ON THE TOOL KIT
|
|
---------------------------------
|
|
|
|
It's useful to realize that the tool kit, with its suspicious looking wires and
|
|
tiny tools, could likely attract the attention of the inspectors at airline
|
|
security checks. A smile and a reasonably good attitude are definitely the way
|
|
to go when they start pulling your suitcase apart and looking at you strangely!
|
|
|
|
|
|
---
|
|
END
|
|
---
|
|
--
|
|
Jeff Sicherman
|
|
up the net without a .sig
|
|
|
|
|
|
|