Come across a fax issue with an ATA190 device. The issue was the fax machine wouldn’t answer any calls. I could see the ATA190 would be in a ‘ringing’ state, however the fax machine wouldn’t budge. The calling endpoint would just ring out.

Checking the setting on the ATA190 as per below, the Ring Voltage set to 85 V and Ring Frequency set to 20 Hz.

All that needed to be done in this case was to adjust both the Ring Voltage and Ring Frequency for the Fax Machine to essentially be compatible and pickup the incoming call. Thank you TAC.

On ATA190 web GUI, navigate to Voice -> Regional -> Ring and Call Waiting Tone Spec

Modify the below values, save the configuration, then reboot the ATA190 device.

Ring Voltage : 70V
Ring Frequency : 25 Hz