Digital vs. Analog Phone Lines Never connect your modem directly to a digital line.
Modems work on analog, or sound, signals.
The wattage from a digital line is too high for a modem. It will destroy your modem's circuits and possibly take down the hotel phone system. This is very important to remember because digital phones are becoming increasingly common in offices, hotels, and universities. A digital line may be revealed by the presence of a digital display or by extra buttons for voice messaging, room service, a radio, alarm, or light control. Travel specialty companies sell line-testers.