| 单词 | ring tone |
| 释义 | ring tone Also known as ringing signal and ringing tone. An audible indication to the called party of an incoming call.The nature of the ring tone varies. In the United States, Canada, and other countries in the North American Numbering Plan (NANP), the traditional ring tone is generated by two metal bells mounted inside the telephone set.The ringer is activated by a current of approximately 90–110 volts at 20 Hz generated by a central office-based ringing machine and sent across the copper local loop at a cadence of approximately two seconds on and four seconds off. Contemporary telephones generally dispense with metal bells in favor of various microprocessor-generated ringing signals, and there may be several from which to choose. Personalized ring tones recently have become popular, especially with respect to cellular telephones. Dozens of music genres and hundreds of selections are commonly available for both the ring tone of the cell phone and the ringback tone. See also ringback tone. |
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