I have had mixed luck with Pccharge phone line backup and thier tech support seems to give different ways to do it. Today I got the easiset instructions for USR phone line backup.
Go to setup>modem> switch to manual modem setup> set the baud Rate to 1200 and set the appropriate Port. Under the MODEM INITILIZATION option select WH1. Save. it should initilze the modem.
Now to test… Go to credit card company>EXTENDED>Switch to DAILUP and run card.
it should work. Switch back to TCP/IP and check the use dail up modem for Backup.