Setting Up Protocols Via At Command Strings - Multitech MultiModem MT5600ZDXV Owner's Manual

Table 2-1. Setting Up Protocols via AT Command Strings
4 If the modem reports NO DIALTONE , check that the modem's telephone
line cable is connected to both the modem's LINE jack (not the PHONE
jack) and the telephone wall jack. If the cable looks secure, try replacing
it. If that doesn't work, the problem may be in your building's telephone
installation. To test the building installation, plug a telephone into your
modem's telephone wall jack and listen for a dial tone. If you hear a dial
tone, your modem may be installed behind a company phone system
(PBX) with an internal dial tone that sounds different from the normal dial