The SIDH (System IDentification for Home System) in your cellular telephone tells the cellular system what cellular carrier your cellular service originates from. This is used in roaming (making cellular calls when in an area not served by your cellular provider). Every geographical region has two SIDH (System IDentification for Home System) codes, one for the wireline carrier and one for the nonwireline carrier. These are the two companies that are legally allowed to provide cellular telephone service in that region. The wireline carrier is usually your local telephone company, Read More

A PIN, or Personal Identification Number, is a number that is used on some SIM cards to prevent unauthorized use of the cell phone it is located in. PINs are not used by all SIM cards and may need to be setup before they can be used. A PIN is generally between 4 and 8 digits long and may consist of a “PIN1” for locking the phone itself as well as a “PIN2” for locking certain features that the phone has access to. However, emergency calls can still be made Read More

The telephone Network Interface Device (NID) is what connects your home telephone lines to the telephone company’s network. It is usually a small gray box located on the exterior of your home. It usually contains a modular phone plug that you can use for testing the line. They need both inside testing and outside testing. In some older installations, you may not have a NID. Instead, you will find a “protector block”, a small plastic covered box where the cable coming out of your house connects to the phone company’s Read More

Most people understand that using their cell phone in their basement or in an office building can be a futile act because the signal is simply not strong enough. Therefore, it is difficult to make phone calls and, more importantly, to send text messages. All the concrete and walls around you make it difficult for the signal to be received in a strong enough amount to properly allow for information to be transmitted. A femtocell, though, is a new type of technology that acts like a relay station for the Read More

A conference call center is a centralized location where an individual, small business or large corporation can go to conduct a conference call or to allow other parties to join a conference call or listen in to a conference call. A conference call is a telephone call in which more than one party can listen in to a telephone call or participate in a telephone call. Conference calls in which other parties join the call just to listen to the audio of the call and not to participate or interact Read More

A Black Box is an electronic circuit (normally a resistor and capacitor placed in parallel) that can be placed on a phone line to provide a free phone call on legacy telephone systems. In order for a call to be free for the originating and receiving station, both have a have Black Box or other method implemented to avoid call charging. The box was a popular method used by telephone phreakers from the 1960s to 1980s. An alternative use of the Black Box is to incorporate them into the incoming Read More

An InterLATA or long distance call refers to a telephone call made between two separate LATAs. LATA (Local Access and Transport Area) is a term used to describe the area that a local telephone company manages. Markets, rather than geographical areas, define LATAs. Therefore, LATAs can cross over state borders and use multiple area codes. An InterLATA requires IXC (Inter-eXchange Carrier) use, which is a company setup to handle long distance calls. How InterLATA Works InterLATA consists of various equipment and companies that transfer calls across two or more LATAs. Read More

The main mobile telephone systems in the last twenty five years have been: YearMobile Telephone System 1981 Nordic Mobile Telephone (NMT) 1983 Advanced Mobile Phone System (AMPS) 1985 Total Access Communication Systems (TACS) 1986 Nordic Mobile Telephony (NMT) 1991 American Digital Cellular (ADC) 1991 Global System for Mobile Communication (GSM) 1992 Digital Cellular System (DCS) 1800 1994 Japanese Personal Digital Cellular (PDC) 1995 Personal Communications Service (PCS) 1900 – Canada 1996 Personal Communications Service (PCS) – USA Analog and Digital Mobile Telephone Technologies Mobile telephone systems are either analog or Read More

Caller ID displays the phone numbers of in-coming calls. There are times when a person may want to prevent his/her phone number from appearing on the recipient’s Caller ID. To temporarily prevent your phone number from showing up on a caller ID, use the following directions: 1. Dial *67. 2. Immediately after dialing *67, dial the complete 10 digit phone number. This sends the Caller ID selective blocking command to the telephone service provider. It is a free service. This will only work if you are calling private and business Read More

Here are the frequencies for the first generation 46/49MHz cordless phones. Channel Handset Frequency Base Frequency 1 49.670 46.610 2 49.845 46.630 3 49.860 46.670 4 49.770 46.710 5 49.875 46.730 6 49.830 46.770 7 49.890 46.830 8 49.930 46.870 9 49.990 46.930 10 49.970 46.970 900MHz Cordless Phone Frequencies Second generation 900MHz cordless phones have been allocated the frequencies between 902 and 928MHz, with channel spacing between 30-100KHz. The following are some examples of the frequencies that example cordless phones use: Panasonic KX-T9000 (60 Channels) Base Frequency: 902.100 – Read More