Some telephones, depending on the brand and model, have the intercom function, which allows to begin communication by sending the signal. When the signal comes, the telephone set rings a signal different from the standard ring tone call. After that the telephone temporarily switches off from the telephone line and works as an intercom.
Technicall USA Inc ia a voice over IP and Wireless Data Networks provider located in, Salem, Oregon. With our TechniCall products you can plug your normal telephone in and get connected to anywhere in the world through your existing broadband connection.
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