Just in case . . .
3.1
7
How your fax machine works
The concept of how a fax machine works is simp le. H er e’s a simple analogy. Let’s
say you want to mail a gift to a friend:
• You take the item, wrap it and send it.
• Days later, your friend receives the package, unwraps it and uses it.
Now, let’s apply that to fax communication.
You put a page into your fax machine’s feeder and call a fax number. Your machine
makes a satisfactory connection with the other machine, and then . . .
• An image scanner in your fax machine examines the information on the page.
That’s how your machine takes the document.
• Your fax machine translates the scanned information into a numeric code and
compresses the code for the fastest possible tr an s mis sion speed. That’s how
your machine wraps the document.
• Finally, your fax machine sends the compressed code. That’s how your
machine sends the document.
On the other end of the line . . .
• The remote fax machine receives the code.
• The remote fax machine uncompresses and deciphers the code, turning it into
a representation of the scan your machine made.
That’s how your machine unwraps the document.
• The remote fax machine prints the representation.
Now, the recipient can use the documen t.
. . . and that’s how fax work s!
The only difference between a regular telephone call and a fax call is the cont ent of
the transmission:
• On a regular call, your telephone send your voice.
• On a fax call, your fax machine sends a coded image.
The way fax machines work is regulated closely by international standards applied
by the International Telecommunications Union (ITU), an agency of the United
Nations. These standards ensure the compatibility of your fax machine with
millions of other fax machines world-wide. Ho wever, they also limit the way you
can use your machine with a second phone.
None the less , th is is a sm all pric e to pay --- for t he a bility to send documents just
about anywhere on earth!