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    • How to Unlock a GoPhone

      How to Unlock a GoPhone

      GoPhone is the trademark used by AT&T/Cingular to market their pay as you go cell phones. Most customers will eventually want to switch to a more normal post-pay cell phone plan, and many of them will want to take their cell phones with them. Unfortunately, the GoPhones are "subsidy locked." This means that the GoPhones

    • TTY/TDD

      TTY/TDD

      TTY/TDD stands for a group of telecommunication devices that make it easier for deaf and/or mute people to talk over telephone lines. TTY stands for telephone typewriter, teletypewriter or text phone. TDD stands for Telecommunications Device for the Deaf. Usually these devices are all categorized under TTY/TDD. Sometimes TTY means manual devices such as typewriters,

    • How to Add Ring Tones to my BlackBerry

      How to Add Ring Tones to my BlackBerry

      Owning a Blackberry enables its owners to do much more than they could ever accomplish with a basic cell phone. However, one of the most popular features that have carried over from basic cell phone to the BlackBerry is the ability to add ring tones. In earlier models adding ring tones to your Blackberry was

    • How to Dial a DSN Number

      How to Dial a DSN Number

      DSN stands for the Defense Switched Network which is a global phone service used by the United States government capable of both non-secure and secure communications. Traditionally, the DSN network has only been used for voice communications, but in the past decade data and video service have been incorporated into the network through Integrated Services

    • Cell Phone Cloning

      Cell Phone Cloning

      Cell phone cloning refers to the act of copying the identity of one mobile telephone to another. This is usually done to make fraudulent telephone calls. The bill for the calls go to the legitimate subscriber. This made cloning very popular in areas with large immigrant populations, where the cost to “call home” was very

    • How Do Prepaid Phone Cards Work?

      How Do Prepaid Phone Cards Work?

      As more and more people switch to cell phones for communication, many people are opting to use prepaid phone cards rather than signing up for a contract with a service provider. Prepaid phone cards allow users to purchase temporary plans ahead of time and use their minutes from wherever they are without having to worry

    • Forward and Reverse Channels

      Forward and Reverse Channels

      Forward and reverse channels refer to a number of frequencies that are used by a telecommunications broadcast system in order for a telephone tower and a cellular telephone to communicate with each other. A forward channel refers to the frequencies used by a telephone tower to communicate with all nearby cellular phones. Contrastingly, a reverse

    • How to Restore a Blackberry to Factory Settings

      How to Restore a Blackberry to Factory Settings

      A Blackberry is a “smartphone” that integrates a phone, media player, email client, web browser, camera, and personal digital assistant (PDA) in a single device. It has many purposes and allows users to perform a number of tasks such as creating notes, accessing the Internet, and scheduling events. Blackberry phones represent over 14% of the

    • AMPS (EIA/TIA-553) and NAMPS (IS-91)

      AMPS (EIA/TIA-553) and NAMPS (IS-91)

      Mobile Frequency Range Rx: 869-894; Tx 824-849 Multiple Access Method FDM Duplex Method FDD Number of Channels 832 Channel Spacing 30kHz Modulation FM AMPS AMPS (Advanced Mobile Phone Service) was the first cellular mobile system in the United States. AMPS operates as an analog system using 30 kHz wide channels. NAMPS AMPS was later enhanced

    • Ringback

      Ringback

      A ringback number is a number that you call that will immediately ring the telephone from which it was called. In most instances you must call the ringback number, quickly hang up the phone for just a short moment and then let up on the switch, you will then go back off hook and hear

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