Ecm (Error Correction Mode) - Brother FAX-8350P Owner's Manual

3
I N T R O D U C T I O N
When your fax machine is in Fax/Tel (F/T) Mode, it answers with a short
beep. After this beep, the fax machine listens for CNG tones, and then
responds with receiving tones.
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 fax machines can understand how each is
sending and receiving the fax. The handshake cannot begin until the call
is answered, and the CNG tones only last for about 40 seconds after the
number is dialled. Therefore, it's important for the receiving machine to
answer the call in as few rings as possible.
When you have an external telephone answering device (TAD) on your fax
line, your TAD will determine the number of rings before the call is
answered. Pay special attention to the directions in the Installation chapter
for connecting a TAD (or answering machine) to your fax machine.

ECM (Error Correction Mode)

The Error Correction Mode (ECM) is a way for the fax machine to check
the integrity of a fax transmission while it is in progress. ECM
transmissions are possible only between machines that both have the
ECM feature. If they do, you may send and receive fax messages that are
continuously checked for their integrity.
Sufficient memory must be available in your machine for this feature to
work.