This Telstra facility is available to test fax modems and phone lines. Simply fax one page (without header) to 1300 368 999 from the line you wish to test. About 1 to 5 minutes later a return fax of 2 pages will be sent with a report. This will include an assessment of transmission level and line noise level. The transmit level can be changed if necessary. This is S97 on the Banksia PM14.4F, but different on other modems. Details of how to get a manual are also given on the report form, but it will hold up your fax machine for a while!
This facility is only for fax, with a maximum speed of 14400 baud, but it may be helpful to diagnose modem data problems.
Equalisation adjustment is another area of possible adjustment, but we have not experimented with it.