INTRODUCTION 1 - 7
About fax machines

Fax tones and handshake

When someone is sending a fax, the fax machine sends fax calling
tones (CNG tones). These ar e quiet, intermittent beeps every
4-seconds. You’ll hear th em after you dial and press Start/Copy
and they will continue for about 60 seconds after dialling. During that
time, the sending machine mu st begin the “handshake” with the
receiving machine.
Each time you use automatic procedures to send a fax, you are
sending CNG tones over t he phone line. You’ ll soon learn to li sten for
these quiet beeps each ti me you answer a phone on y our fax line, so
you will know if you are receiving a fax message.
The receiving fax responds with fax receiving tones, which are loud,
chirping sounds. A receiving fax chirps for about 40 seconds over the
phone line, and the LCD shows RE CEIVE.
If the fax machine is set to the FAX ONLY mode, it will answer every
call automatically wit h fax receiving tones. If the othe r person hangs
up, the fax machine will cont inue to send the “chirps” for abou t 40
seconds, and the LCD continue s to show RECEIVE. To cancel the
receiving, press Stop.
The fax ‘handshake’ is the time in which the sending machine’s CNG
tones and the receiving machines “chirps” overlap. This must be for
at least 2 to 4 seconds, so the f ax machines can understand how
each is sending and receiving the fax. The handshake cannot beg in
until the call is answered , and the CNG tones only last for abo ut 60
seconds after the numbe r is dialed. So it is important for t he receiving
machine to answer the call i n as few rings as possible.
When you have an external Tele phone Answering Device (TAD)
on your fax line, your TAD will decide the number of rings before
the call is answered.
Pay special attention to the directions for connecting a T AD in
this chapter. (See Connecting an external telephone answering
device (TAD) on page 1-10.)