Fax Troubleshooting on the SPA100 Series

Objective

This article explains how to troubleshoot faxes if the user has issues transmitting or receiving faxes on the SPA100 Series Phone Adapter.  For fax calls to work correctly, both the ATA and the supporting fax machine must be configured correctly.  If the user has any issues with sending/receiving faxes, follow the procedure explained in this article.

Applicable Devices

• SPA100 Series Phone Adapters

Software Version

• v1.1.0

Fax Troubleshooting

Speed of the Fax Machine

Note: The optimal speed of the fax machine is to be set between 7200 and 14400 bps. It is better if the speed is set to 9600 bps with error correction ECM turned off. The modern fax machines have the ECM capability that evaluates the corrupted data in a received frame. If any is detected, then a retransmit signal is sent until a error free frame is received.

Step 1. On the graphical user interface (GUI) of the fax machine, choose Setup > Advanced Fax Setup > Fax speed and enter the desired speed between the given range in the Fax Speed field. Fax machine transmits data at different rates. Verify the speed on your fax machine and make sure it is between the optimal speed range.

Perform a Test Fax

Step 2. Navigate to Tools and choose Run Fax Test to test the fax machine by sending a test fax between the two ATAs.

Save the Configuration file

Step 3. Determine the rate of success when the user transmit or receive faxes and save the configuration if the test perform is successful.

Step 4. Record the statistics for jitter, loss, and delay throughout the time the user monitors the network.

• Jitter —  The network jitter determines how the jitter buffer size is adjusted by the ATA. The jitter buffer controls the rate at which the jitter buffer size is adjusted. The values that can be recorded are low, medium, high, very high, and extremely high. 

• Loss — The loss of packets along the data path which severely degrades the voice application.

• Delay — The time taken from point-to-point in a network.

Step 5. If the user consistently fails to transmit or receive faxes, identify which type of fax machine user has connected to the ATA and then contact Technical Support for more help. Copy the current configuration and send the file to Technical Support.