Forget everything you learned on the Internet!


Most online 'experts' recommend the following (wrong) settings:

  1. Reduce speed to 9600bps
  2. Turn off ECM error correction
Some fax machines call it 'basic' mode, others call it 'low' compatibility. Whatever it's called, you don't want it.

Instead we recommend:
  1. Set speed to 14,400bps
  2. Make sure ECM error correction is enabled

The methods to configure these settings vary from machine to machine, and there are too many variations for us to list here. Some enterprise-oriented fax machines even require a licensed service technician to modify these settings. That being said, here are a few general pointers to help you (or your technician) ensure the correct settings on your fax machine.

Before you start changing your fax machine's settings, call your fax machine using a cell or office phone. you should first hear a clear, continuous fax tone. If the fax tone sounds like it is interrupted at regular intervals, your fax machine needs further adjustment: you can compare it to the .wav files in the attached .zip file. On most fax machines this behavior is triggered when the fax machine's speed is set to 33,600bps instead of 14,400bps, but it may less commonly be labeled V.34 or V.8 mode, which should be disabled.

Now it's time to adjust the fax settings to get them as close to the recommended configuration as possible. Sometimes the fax settings are broken up into component parts, and you can even configure the settings for TX and RX separately. In those cases the TX and RX settings should match.  Other times all of the fax settings are controlled together in a single option. On Brother fax machines, for example, you would need to select 'Normal' compatibility at:


MENU -> 2. Fax -> 0. Miscellaneous -> 1. Compatibility -> 'Normal'

Once you stop hearing the ticks in the fax tone, and you're pretty sure your other settings are configured correctly, you can use our ECM Self Test to verify your fax settings. In addition to testing ECM capabilities, your transmission speed will be listed under "SignalRate".