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    • 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

    • 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

    • IMEI (International Mobile Equipment Identity)

      IMEI (International Mobile Equipment Identity)

      Each GSM and UMTS mobile phone has a unique IMEI (International Mobile Equipment Identity) number. An IMEI number facilitates an important function – it easily identifies a mobile phone being used on a GSM (Global System for Mobile Communications) network. The IMEI is a useful tool to stop a stolen phone from accessing a network

    • What is SMS (Short Message Service)?

      What is SMS (Short Message Service)?

      SMS, or Short Messaging Service, is a text-based messaging service that is used by over 2.4 billion mobile phone users worldwide. SMS allows users to send and receive text-based messages, pictures, videos, and audio clips from other mobile phone users and desktop computer users who have applications that can interact with mobile phones. SMS differs

    • How Cell Phone Tracking Works

      How Cell Phone Tracking Works

      Before GPS started being deployed in the majority of mobile devices sold on the market, the only method available to track a cell phone was triangulating the cell phone’s position using one of several techniques available to law enforcement and other governmental agencies. Today, most cell phone tracking applications work by accessing the GPS location

    • How to Make a Lineman’s Handset

      How to Make a Lineman’s Handset

      This is the “right hand” of both the professional and the amateur lineman. Basically, it is a customized portable telephone which is designed to be hooked onto raw cable terminals in the field and used to monitor the line, talk, or dial out. The monitor function is usually the main difference between the “butt-in” test

    • How to Dial International Phone Numbers

      How to Dial International Phone Numbers

      With the expansion of Voice over IP and cellular phone technologies over the past decade, it has never been more cheaper to call international phone numbers. A common barrier for consumers trying to call friends, family, or business contacts that live abroad is determining how to dial international phone numbers from your country. International Dialing 

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