THE TECHNICAL STUFF

Your computer is a digital device and accomplishes most of it tasks by turning on or off a series of electronic switches. A binary "0" represents a switch that is off and a binary "1" indicates a switch is on. There is no in between designation. A graph of digital code would look like this: 00110100101100001.

The standard telephone system is an analog system, designed to transmit the diverse sounds and tones of the human voice. Those sounds are conveyed electronically in an analog signal as a continuous electronic current that smoothly varies its frequency and strength...what is commonly depicted as a flowing wave.

A modem is the bridge between digital and analog signals. It converts the on-and-off of the digital signal of the sending computer by varying or modulating, the frequency of an electronic wave. It does just the opposite at the receiving computer: It demodulates the analog signal back into digital code. The two terms, MOdulate and DEModulate, give the modem its name.

Modem communications involves three of the least standard elements of personal computers: COM ports, modem commands and communications software. These inconsistencies make it impossible to describe one universal way which all modems work, but the description that follows will be general enough for almost all systems that any of you will experience.

No more geek, techno talk.

THE HARDWARE

There are two types of modems:internal and external. An internal modem is on the inside of your computer and an external modem is located on the outside. They both work essentially the same.

You can tell if you have an internal modem by looking on the back of the computer where all the cables are plugged into. If you see two telephone plug sockets, you have one. While you are back there, look at the other sockets and what is already plugged into them. You should find one or two 'serial ports' and look like this:

______
\ . . . . . /
\ . . . . /

These are 9-pin serial ports and most often labeled COM1 and COM2 or SERIAL A and SERIAL B.

If you do not have an internal modem, you will need to plug an external modem into one of these serial ports (preferably COM2).

Most modems, internal and external, come preset to COM2 by the use of 'jumpers' or 'dip switches'. Check your manual for configuration settings.

Both types of modems have two RJ-11 plugs (sorry about the techno jargon)...telephone plugs. These plugs are labeled 'line' and 'phone'. Plug a telephone line from your wall outlet into the one labeled 'line' and another line from the 'phone' into your telephone. If you have a separate line for your FAX machine, just daisy chain the modem into the FAX line.

I have been told that the modem should be the first device plugged into the wall, but I have so many devices plugged in at home to one line, that it's hard to tell what order they are in...phone, FAX, modem and answering machine, another modem, and on and on and on...

MODEM COMMANDS

Each manufacturer of modem 'chips' uses different language telling the modem how to behave. Some of the command language is quite similar and some very different. This always reminded me of the military codes: Halt, Who goes there?...Roger Marris... Who won the '42 Super Bowl? The Boston Yankees....

Actually, there is some sense to it but it is only necessary to understand that it exists, because of......

COMMUNICATIONS SOFTWARE

All communications programs need to know the directions (settings) to your modem: to fax or dial into your internet service provider (ISP).

In most new systems, the modems are pre-configured, or will install themselves practically.

In Windows 95/98 for example, Modems can be found in the Control Panels (In 'My Computer' on the desktop).

You will know you are in the right location when you see a panel that gives you an option of which COM PORT your modem is at. There will also be another setting to make: the type of modem (who made the chip .... which language to use to talk to the modem)  If you are not sure what type you have but are pretty sure it is not a US Robotics, select the HAYES setting. Almost all other chip makers use the HAYES language to communicate with their modems. Your modem documentation will tell you what you have.

If you are working with Windows 95 or Windows 98, your modem software should be installed with your system, or will install automatically when you connect or insert the modem card into the PC.  The modem will generally come with software.  Install this by inserting a disk when prompted, or by using the 'setup' or 'install' program on the disk or CD, and the 'drivers', or software Windows needs to communicate with the modem will be installed. 

If it's more complicated than this, call your technical support person!  The TOCP project staff can also help. Chip Sawyer at wsawyer@zoo.uvm.edu , or David Deutl at ddeutl@zoo.uvm.edu are both qualified to answer your questions.

Your modem should function now.  One way to test - Go to the Control Panels.  Open Modems.  Click on the Diagnostics tab.  Select the modem in list, and then click on More Info.  If Windows is communicating with the modem, you will see a lot of commands listed and OK's.  If nothing happens, there is a problem.  Again, it is best to check with your technical support at this point

Once your modem is installed and the software is configured, you will not need to go through these steps again.

BUT....DO NOT throw away either set of documentation or put it in a 'special' place where it won't get lost. ...I do that with my keys all the time....I must have a dozen sets stacked in places I don't remember.

Keep all your manuals together, near your computer, and.....

Write down the all of the settings and put them in your 3-ring note book. I remembered that you have one.

All of you already have your modems connected and your software working or you would not be reading this by e-mail. But you still get......

Homework ! !

Go into your Control Panel and find the Modem settings (properties) and write down the directions on how to get to the properties along with the name of the modem and the file name and date of the driver software (Diagnostics area), and put it in your 3-ring note book (Cheat....in the menu bar, HELP, ABOUT)

ROADMAP: Copyright Patrick Crispen 1994, 1995. All rights reserved. Modified by permission by UVM Extension, 2001.