3Com DIGITAL MODEM User Manual

Contents

2-18 CHAPTER 2: INSTALLING AND CONFIGURING THE DIGITAL MODEMCAUTION: The 3Com Impact digital modem is designed tooperate with telephones that are compatible with the originalAT&T 2500 touch-tone telephone standard. 3Com guaranteesproper operation of up to three compatible touch-tone deviceson the Phone Out port. The digital modem is designed toprovide power and ringing for these three devices on up to 100feet of AWG 26 or heavier AWG wiring. Although the digitalmodem may function satisfactorily at longer cable distanceswith more than two attached telephones, proper operation atlonger cable distances is not guaranteed in all situations.Specialized telephone equipment, most notably speakerphones that draw significantly larger amounts of power, maynot work at all on the digital modem’s Phone Out port. Thesedevices do not conform to the loop current (power)specification of the 2500 touch-tone telephone standard, andtheir operation is not guaranteed.Placing Calls Using the Phone Out PortTo place an outgoing call, simply take the telephonehandset or external fax machine off the hook, wait for a dialtone, and dial the destination telephone number.Receiving Calls Using the Phone Out Portlncoming calls to the telephone number assigned to thePhone Out port ring at the Phone Out port unless you arebusy on another Phone Out port call. If the port is busy, theincoming call is automatically disconnected.If you have a digital modem with an internal analog faxmodem (models 3C872 and 3C877) you can have calls routedto the internal analog fax modem when the Phone Out portis busy. To do this, the digital modem must be configured toallow a call to be routed to both the Phone Out port and theinternal analog fax modem, as described in the section“Configuring the 3Com Impact Digital Modem.”