What is a Ring Back Tone? September 24, 2006Posted by healthyself in 40 Hz, 440 Hz, 480 Hz, Blogroll, Cell phone safety, Cell Phones, Definitions, Electromagnetic pollution, Electromagnetic waves, Electrosensitivity, Electrosmog, Environment, Frequencies, Hearing, Lifestyle, Mobile Music, mobile telephones, Music, Pulsed Radiation, Sound, Telephony, Tone, Waves.
“A ringback tone, or audible ringing tone or ringback signal, is the audible ringing that is heard on the telephone line by the calling party after dialing and prior to the call being answered at the distant end. The ringback tone is different in various countries depending on the requirements for the ringback specification in those countries. … the standard ringback signal is generated by summing a 440Hz tone with a 480Hz tone and applying these to the telephone line in a 2 second on and 4 second off cadence. The tone combination produces a warbling “ring… ring…” sound, caused by the 40Hz beat between the two. Most other countries use a single tone, …The ringback signal may be generated by the called-party servicing switch or by the calling-party switch, but it is not generated by the called telephone instrument. It is generally started and stopped at the same rate as the ringing signal itself but perhaps out of phase.”
In recent years, “personalized ringback” tone has become globally popular. With this feature, callers will hear an audio selection applied to the telephone line that has been previously determined by the called party. Audio selections can include music, messages, and special effects. Equipment is installed in the telephone network to enable replacement of the standard ringback tone with a personalized audio selection. ..Various companies supply personalized ringback equipment for mobile phone and landline telephone companies….The use of such nonstandard telephony signals can cause problems with automatic dialing equipment such as faxes and modems, however lines intended to receive such data telephone calls normally have the proper ringback tone. In addition, a caller may define specific users to whom the personalized content will be played. Other callers will hear the “traditional” ringback tone.”