Brother Fax-615 - Manual (Page 10)

What is the Fax “Handshake”?
The calling machine sends CNG tones (beeps) and the receiving machine sends receiving tones
(chirps). During the handshake these tones must overlap for 2-4 seconds so the fax machines can
set up protocol. The sending machine states how it is sending the message; the receiving machine
answers whether it is capable of receiving that way. The sending machine’s CNG tones continue
for only 30 seconds after the number is dialed. Calls must be answered within 4 rings (20-22
seconds) or less, because the handshake can not begin until the call is answered. With 4 rings,
only 8-10 seconds are left for the fax machines to hear their tones clearly and communicate.
Timing is crucial.
When you have a telephone answering device (TAD) on your fax line, you can set the TAD to
answer in 4 rings as long as you record a 5 second silence as the beginning of your OGM (outgoing
message) (See page 7-10 for more information). This will prevent the OGM from covering up the
fax tones during the 8 seconds that are left for the handshake. As soon as your TAD answers a
call, your fax machine will listen for fax tones for 30 seconds. So you must limit your speaking to
20 seconds (25 second total OGM). Since many people dial manually without realizing they are
not sending fax tones, you should give your Remote Activation Code (*51) as the last part of your
20 second Message. For example: “After the beep, either leave a message or send a fax by pressing
>1^51.” (See page 7-10 for more information.)
What Causes the Transmission Verification Report to Print “Result: NG”?
During the handshake, the document(s) you are sending begin to roll through the feeder and stop
until the handshake is completed and the machines are ready to send and receive the data. Ifthere
is noise or static on the phone line or if the machines do not agree on protocol, they drop their baud
rate to the next lower level and try again. The initial baud rate is 14400, then 12000 (Only for FAX-
725M), 9600, 7200,4800 and finally 2400. Transmissions as low as 2400 baud can be successful.
So, do not stop your machine. If the transmission fails, a Transmission Verification Report will
be printed automatically with “Result: NG”. This usually means the transmission was “No Good”
because of temporary noise or static on the phone line. Try to send the fax again. Also, you may
try sending a fax to other locations to see if the problem is on the phone line at your end.
Is This a Fax Call?
There are three signs that the call you answered is a fax. You will hear either soft intermittent
beeps (Automatic transmission), silence (Manual transmission) or the voice of someone telling
you he/she is trying to send you a fax (Manual transmission). Do not hang up the handset. It
is very frustrating for the person who hears you repeatedly answer and hang up. People who dial
manually are waiting to hear fax tones before pressing START. You must activate your fax
machine to take over the call before you disconnect the line by replacing the handset.
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