http://www.qdeck.com/fish_brochure/modems.html (Einblicke ins Internet, 10/1995)The other part of connecting to the Internet is getting your computer connected to it. Unfortunately, this isn't as simple as connecting 2 cans with a piece of string and attaching them to your PC. More often than not you will have a local dial-up line, and this means a modem.
The word modem is conveniently derived from MOdulator DEModulator and is a handy way of using up extra capital letters when writing about it. The modem's job is to convert the digital "on and off-ness" of the computer to the high pitch wailing that the phone lines understand.
If you have ever accidentally called a fax machine you'll know exactly what that wailing is (and you'll know to dial more carefully in the future). The modem connects to your computer at the back. Not at the back of the room, but at the back of your computer (please try and keep up).
On the IBM PC and its compatible friends, the modem connects to the serial port. This isn't a port like, say, Pearl Harbor. There are no ships in your computer's serial port, although it is probably worth getting it looked at if you get the Queen Mary knocking on your door.
You connect it to your PC with the cunningly named Modem Cable, which should come with the modem, but, it you don't have one, it is reasonable easy to buy one from a computer store. The only thing you need to know is if your PC has a 9 pin or a 25 pin serial socket. As you may have gathered, this refers to the number of pins in the socket and is not a secret code at all.
Some cables have a 9 pin and 25 pin connector on them and, even if you have the wrong one, it is easy to get a converter. The serial port is sometimes labeled Serial Port (very helpful) or just Serial (helpful), it is also sometimes labeled as a series of ones and zeros (helpful-ish). If you have a little icon of a ship you should complain.
You can of course buy an internal modem that fits inside your PC. You don't have to be a rocket scientist to do it, but if you were say, a dishwasher scientist you should think twice. Internal installation can prove difficult and is only recommended for the experienced PC user (or the terminally foolhardy).
The modem's speed is important, too: for the Internet you should be
looking at an absolute minimum of 9,600 bits per second (newcomers
shouldn't worry what exactly they are bits of, just keep the number in
mind). It is recommended that you aim for 14,400 bps and above
though.
The modem then plugs into the telephone socket. You can plug it into your stereo if you want, but it will probably blow up your house.
You are now ready to go on-line. A flying helmet and goggles are recommended from this point onward.
If you are connecting to an analog telephone line (most dial-up connections) or leased line you will need a MODEM. There is one overriding criteria which should govern your choice of modem, buy the fastest throughput modem you can afford. MODEM throughput is measured in the number of bits of data it can transfer per second. The faster the modem, the faster data will appear on your computer and the smaller your telephone bill. internal modem
The difference between fast and slow modems can be as much as 16 or 32 times. Coupled with speed is also the ability to automatically correct errors in transmission and actual performance and reliability. All in all this is a complex subject and you will need good advice or to read up on it before purchasing.
If you are connecting to a digital line, fiber or ISDN you will need a terminal adapter. Terminal adapters are rather specific and best sorted out with your network vendor.