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WORLD WIDE PHONE
GUIDE
What you need to hook up your modem just about
anywhere!
Introduction
This is a guide to some typical issues that may arise when
you try to hook up your modem in a different country. It includes a table
of telephone plugs used worldwide, ways to deal with hard
wired phone systems, and how to handle special situations
like digital phones and tax impulses. This is intended especially for world travelers and
road warriors, although the information here can also be useful for people who
have purchased and/or moved computer equipment from one country to another. If you need to
find an item mentioned here, check the list of sources.
First Things First
The first thing I do when preparing to hook up in a new location is test
the phone line. I may need a plug adapter to do this, as discussed in the following
section. I use a line tester sold by IBM as a Modem Saver, but similar
devices are made by others. The main purpose in testing the line is to establish whether
it is an analog line, or a digital line. Digital lines
may present a special set of problems, so you need to know this right away.
Phone Plugs
One of the most obvious incompatibilities you are likely to
notice when hooking up your modem in another country is the type of plug used at the wall
jack. (If there is no plug, this may also a problem; this is discussed in the hard wired section).
Most developed countries have their own specific type of
telephone connections. There are a few dozen types of plugs used around the world, as
shown in the table of worldwide phone plugs.
The American-style plug the US RJ-11 is the closest
to what might be considered an international standard. This type of plug been
adopted in many countries worldwide, including North America, Greece, Spain, Ireland, most
of Central America and the Far East.
In countries where the table shows
the US RJ-11 system, this jack will be found at least in major hotels, if not throughout
the country. Older phones may be hard wired or may use
an older type of connector. (In this case, you will need to use special equipment
described below.)
In my travels, I have noticed with increasing frequency cases
where the wall plug may be been of a local design, yet the connection at the back of the
phone is a US RJ-11. Or, even if there is a local type plug at the wall, in some places
that plug may accept an RJ-11 line from the phone. If you're really lucky, the phone may
even have a RJ-11 data port. (You know you're living right when the phone has two lines
and a data port.)
Since many portable computer modems (notably the Megahertz
X-Jack) are designed around the RJ-11, hooking up is very easy. If you can't connect at
the wall, but have an RJ-11 at the back of the phone, simply unplug the line from the back
of the phone and snap it in to the X-Jack. If your modem has a line that terminates with
an RJ-11, an in-line coupler will let you tie the line from the phone to your modem. If
you have an extension phone cord and a dual jack adapter, you can keep the phone and the
modem plugged in simultaneously to keep from switching the line back and forth between
voice and data calls.
However, you could just as easily find that the line from the
wall has a local jack and is hard wired to the back of
the phone. The quickest and easiest solution to this problem is to obtain an adapter that
will let you connect the phone plug from your modem into the wall jack at your
destination.
You have two basic choices here. If you're like me (a scary thought) you want
to be able to plug in and log on to your mail server the minute you get to the hotel room,
even if it was 1 a.m. when you landed in Muscat or Singapore. To do this, you will need to
be prepared for whatever outlet you may encounter at your destination upon arrival. This
is where I can help. Consult the table of worldwide phone plugs
to learn what type of plug(s) may be used where you're going. Then contact one of the
various sources that sell such items.
Those of you who take a more laid-back approach to things can
get a good night's sleep, evaluate your needs, and then saunter out to a local merchant in
search of the proper adapter. Examples of places where you might find what you need are
also listed on the sources page. You might even be able to get
one from the hotel...but don't count on it.
A Quick Word About Dial
Tones
So you've got your adapter and it's plugged in. You're set,
right? Well, maybe. Dial tones can vary from country to country, and your modem may not
recognize the tone at your new destination. You can get around this by adding a command to
your modem setup string telling it to ignore the dial tone. On Hayes command set modems,
this is done by inserting X1 after the initial AT command. Check your modem manual before you leave
to see if it's the same for yours. Either set this string ahead of time, or write it down
so you'll have it if you run into dial tone problems (that way, you don't have to haul the
entire manual with you).
| More about dial tones... One of my trusty correspondents wrote:
"...you mention using the Hayes
command X1 to force the modem to connect without waiting for a dial tone. Setting to X1
also strips a lot of the error correction and data compression that your modem will
normally use. (Not sure all of what it strips off the top of my head)... Now, some newer
modems will need you to consult with your manual to know what level of
"intelligence" you need set your modem to in order to suppress checking for dial
tone, and in this case X1 or even X0 is a sure way of getting it to work, but in most
cases you can set it to X3. X3 was generally [meant to] suppress checking for dial tone
without disabling any other functionality in your modem. It should work just fine with any
14.4 or probably 28.8 modems out there, though I can't say for absolute sure."
None of this stuff is a sure bet,
but he reinforces my point: consult your modem manual before you leave to
know what your options are.
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What if it's Hard Wired?
You may find that instead of a wall jack, all you have is a
line coming out of a plate in the wall. Upon closer examination, you find that there is no
jack at the back of the phone, either: just the phone cord disappearing inside the case.
As you probably know, this is called a hard wired phone. This can be a
nightmare, but it need not be a deal breaker if you've got the right tools and equipment.
Sometimes, even though the phone may be hard wired to the
wall, there is a modular connection between the phone and the handset. If you can
disconnect the handset cord from the phone, then you can use a digital line connector as described below. This will work
even if it's an analog phone line. It's a neat and effective solution, although in my
opinion these things tend to be overpriced. There isn't much to them, yet they go from
anywhere between $65 and $140 US.
However, this won't work either, if the phone is also hard
wired between the base and handset. In this case, here are your options:
Use an acoustic coupler.
Remember these? Maybe you're not old enough. This is how people hooked up their modems
before phone systems became modular. You insert the handset into a cradle which uses the
handset's microphone and ear piece to send and receive data signals. This will also be
your best bet if you need to connect through a public pay phone, since those with data
jacks are still rather rare. I do not personally carry one of these, since they are not
only somewhat expensive ($75-100 plus US) but are also on the bulky side and usually require
batteries. However, they do work, and can be effective in a situation where the phone and
handset are both hard wired. Some people prefer them because they are
more-or-less a universal solution, eliminating the need for plugs and
wiretaps. This is also the only solution should you have the misfortune
to encounter a hard wired digital phone (although I think such
beasts are rare).
| More
about acoustic couplers...
Another trusty
correspondent wrote:
"My two cents if you care to read
them: I can appreciate your concerns about cost of acoustic coupler, but it seems to be a simple, single solution to all possible
problems. In the end, for me at least, it's cheaper and
easier."
And yet another wrote:
"I find myself using the coupler 80%
of the time. It just works the same everywhere...by the second
try, anyway. On previous trips, I used to take apart the wall (or the
phone itself so I didn't have to crawl on the floor) but now I usually
find the coupler the quickest way to get online. Since I generally
just use it for email, the connection speed is not so important.
One further note: The coupler was having problems mating with the modern
(tiny) mouthpieces on some newer handsets -- mainly in Germany. I
had to improvise a couple of times to get the seal, even with the extra
mouthpiece seal that comes with the coupler."
And finally:
"Is there one more reason to
recommend an acoustic coupler for overseas use? I've traveled
several times during the past year or two in countries that use tax
impulses but the impulses have never posed a problem with my
connection. My theory is that the tax tones get filtered out
because I use an acoustic coupler. The tones use high frequencies
(12 to 16 kHz) that are barely within the audible range. The telephone
handset can hardly be considered a hi-fi device and thus may not
reproduce such high frequencies (or perhaps the tones get lost by the
coupler itself)."
There you go. As they
say, your mileage may vary. It doesn't hurt to be prepared for
everything.
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Practice basic wiretapping.
Instead of an acoustic coupler, I carry a length of phone cord that has a modular
connector on one end and a set of test leads on the other. A test lead is nothing more
than a short length (12", or 30 cm) of small wire with a spring clip (known as an
alligator or crocodile clip) at each end. If there's a wall plate, I pull it off (I also
carry a Leatherman mini-tool which acts as screwdriver, pliers, knife and performs
other functions). If there is a terminal block inside (where the line from the wall is
connected by screws to the lead to the phone instrument), I hook the spring clips onto the
screws. Before I dare hook this to my modem, I snap an in-line connector on to the RJ-11
connector at the other length of the phone cord. Then I use my line tester to make sure
the line is good.
But there may not be a terminal block, or perhaps the screws are recessed and can't be
reached by the spring clips. Then I must perform minor surgery. If there is no terminal
block only a relatively large wire running into the wall I carefully strip
the insulation from the wire. This exposes the conductor wires inside. If there is a
terminal block, the conductor wires will probably already be exposed, although you might
need to remove some insulation to make them more accessible. Most phone wire has four
conductors, although in a single-line analog system only two wires are usually used. These
are called tip and ring
wires. Tip is the positive lead, and ring
is the negative lead. Traditionally, in the US and Canada, tip was green and and ring was
red, although in modern construction you're just as likely to find twisted pair where
blue/white (blue wire with a white stripe) is tip and white/blue is ring. Other countries
have different wiring schemes. For instance, I've read that in the Netherlands, tip and
ring are red and blue, respectively. In Germany, they are red/black and red, and in the UK
they are white and blue. But these rules may not always hold true, and many other
countries may have no uniform method at all. The point is: you will probably need to rely
on a combination of intuition, trial and error and your line tester.
What I do is remove just enough insulation from the conductor
wires (these are small wires) so that I can clamp the spring clips to them. Again, I hook
the test leads to my extra length of phone cord and use the line tester to make sure I've
got a proper connection before I hook it to my modem. I also carry a small spool of
electrical tape so that when I'm done I can properly repair the cuts I made in the
insulation. If you must resort to this type of action, please be responsible and patch it
up when you're done. As I said, this is a form of surgery. No responsible surgeon would
cut open a patient without being prepared to seal the incisions upon completion.
| And now,
maybe a better idea...
Yet another correspondent
contributed this ingenious gem:
"Why not carry a couple of safety
pins with you, and poke them through the insulation and into the wire
inside. Then clip onto the pins. Its much faster, and
doesn't require repair."
Wow! I wish I had
thought of that... |
Another skill that you should practice before you set out on your trip
is that of making a manual connection through your modem. In other words, you dial the
call yourself (rather than letting the modem autodial) and then use your software to
connect the modem manually once you hear the carrier tone. See the phone at the left?
While this looks like (and indeed is) a relic of the past, it was nevertheless encountered
at an otherwise posh and modern resort in South America in early 1996! While most
software and modems can be set to use pulse dialing when using old rotary systems like
this, the setup at this hotel presented a special problem. International calls had to be
placed through the switchboard. To obtain a local outside line, I had to press the button
to the lower right of the dial (a task which required a surprising amount of physical
effort). The only way I was able to make this work was to 1) pick up the handset and give
a hefty push on the outside line button, 2) dial the local access number for my provider
myself using the rotary dial, and 3) connect the modem manually with my software and hang
up the phone once I obtained a carrier tone. Had I not had a local access number, I would
have had to have the switchboard place the call, and then connect manually. (Before any of
this could occur, I might add, I had to practice basic
wiretapping as described and shown above.)
Even if you never encounter a phone system as unusual as this
one, you still might find situations that require making a manual connection. If you are
trying to work through a digital phone system, you might
find that you are unable to autodial using either a digital connector or acoustic coupler.
The solution will be to connect manually. Even the public data phones I've
seen in the U.S. expect you to make a manual connection after you've dialed the call.
Fortune may smile on you, and you may never encounter a
situation that requires connecting manually. However, if you want to increase your chances
of connecting successfully from virtually anywhere, become familiar with hooking up
manually by practicing at home before you leave. It will save you frustration (and the
expense of many fruitless phone calls) if you should unexpectedly run into a situation
that requires it.
Digital Phone Systems
Many office phone systems are digital, and you will find
hotel systems that are digital as well. A digital phone system is an internal system (a
system within a building, office, hotel, etc.) that uses electronic switching. A PBX
(private branch exchange) system is an example of a digital phone system. You may find
that the system is digital but the phone includes an analog RJ-11 data port, which makes
it all very easy. Otherwise, digital phone systems are likely to be a problem when you try
to hook up your modem. At best, you will get a no dial tone message when you
hook your modem to a digital line. At worst, you will destroy your modem. PC card (PCMCIA)
modems are especially vulnerable to this. The reason is that digital systems operate at a
voltage level in excess of what most modems are designed to handle. The line tester I
mentioned earlier tells me if it's a digital line (the reason it's on my list of highly recommended equipment). If for some reason
you don't want a line tester or can't get one, then a regular residential-type telephone
will work as a substitute. If you plug a regular phone into a digital system,
you will not get a dial tone. Presuming the phone that normally goes into that jack works,
this is a good indicator that you have encountered a digital phone system.
There are two ways around this problem. First, you can use a digital line connector, which is a term I use here to
describe a simple device which goes between the base and handset cord of the telephone and
lets you hook your modem downstream of the phone line, where the signal is analog. Not
long ago these things were scarce, but now there are a variety to choose from (see the sources page). Digital connectors usually require a 9-volt battery,
and may come with an optional AC power adapter. Unlike many computers, the wall
wart power supplies furnished with these devices are normally not
auto-sensing or designed for foreign travel (i.e., capable of switching between 110
or 220 volts). So you may need a voltage adapter, and perhaps a plug adapter (see the World Wide Electric Guide for more on this subject). I don't
usually travel with the AC supply, but I always take some spare 9V batteries.
If the phone is hard wired between the base and the handset,
you will need to use an acoustic coupler. These usually
also require one or two 9V batteries (or perhaps AA batteries) to operate.
ISDN Lines
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ISDN Adapter
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ISDN stands for Integrated Services
Digital Network, another type of digital phone connection (however, an
office/hotel phone system that is digital is not necessarily ISDN).
ISDN allows phone and data communications simultaneously over the same
line, with data transfer much faster than analogue lines. At one
time, ISDN was touted as the wave of the future in the US, but it has
since been surpassed in both speed and popularity by cable modem and DSL
broadband connections. ISDN is still widely used in Europe,
especially the Scandinavian countries. Many modems sold in Europe
are a combination of standard modem and ISDN adapter. That's not the
case with modems sold elsewhere, however. While most hotels with
ISDN connections will probably have an analogue line available, I've seen
at least one hotel in Norway where that wasn't the case. If you run
into a place like this, you will need to obtain an ISDN adapter -- my
hotel had them available from the reception desk (shown at left), though they only had a
few of them and some of those didn't work properly. |
Tax Impulses
Some countries use what are called tax impulses
on the phone lines. These are high frequency pulse signals which are used to meter local
phone usage and assign charges. They may interfere with your data connection and keep you
from making a successful hookup. You may encounter tax impulses in Austria, Belgium, the
Czech Republic, Germany, Spain, and Switzerland. To get around this, you may need what's
known as a Tax
Impulse Filter. This a small device which plugs into the phone
line between the wall and your modem. But maybe not...read the box below:
| More about Tax Impulses... Another correspondent contributed this:
"I lived in Germany for 4 years, and I was able to set
my (U.S.) modem (USR Sportster) to skate over the tax impulse by setting the S10
register (carrier loss wait time) to something much higher than the default 0.7 seconds.
"It works to disable it completely, but I was able to
set it to 2.4 seconds (higher than the impulse time by a factor of 2-3, but not disabled)
and still function. Depending on the time of day, day of week, and distance of call,
the pulses were as little as once every 6 seconds or as long as once every 12 minutes.
There was data loss for each pulse, but at least I wasn't disconnected.
"The filters that were available were expensive, and did not prevent the data loss
that occurs using my "cheapskate" method, either."
I haven't traveled to tax-impulse countries
lately (tax impulses have been removed in some places) so I can't comment. This
correspondent raises a point I made about the digital connectors: there is usually
not much to them, but they're still pricy. His solution requires familiarity with how to
customize your modem. This may not be enticing for the novice or casual
user, but it would be worth a try for an advanced user. -- S.K.
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Will This Stuff Guarantee a Connection?
Sadly, no. In some parts of the world you will encounter
phone systems that have not been modernized, are overtaxed, or simply have technical
problems that prevent you from making a satisfactory data connection. Sometimes, sheer
persistence will prevail, since the conditions that prevent you from making a connection
on one attempt may clear up on your next (or your 40th) try. Most of the places I've been
(all continents, except for Africa and Antarctica) have not posed any overwhelming
problems. Rio de Janeiro, Brazil and Jakarta, Indonesia were places that tested my
patience. Nevertheless, after repeated tries, I was able to get online at least long
enough to send and receive e-mail (though sometimes 2400bps was the fastest connection
available). The only place from where I have never been able to make a modem connection,
after days of trying, was the Greek island of Mykonos (it's a nice enough place, so I
really didn't mind). When you travel, be aware that there are many areas of the world
where the local phone system may still be light-years behind the technology you're
carrying in your briefcase. In some cases, you might be better off using a
mobile phone.
Highly Recommended:
May also be needed:
Where can you find this stuff? Take a look at
the list of sources.
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