A tri-band phone operates at three supported frequencies, such as 900/1800/1900 MHz or 850/1800/1900 MHz. A dual-band phone operates at two frequencies, such as 850/1900 MHz or 900/1800 MHz.

GSM handsets must meet the following criteria: GSM 1900 megahertz (MHz). Federal Communication Commission (FCC) Approved. The handset is not locked to another carrierâ??s network

Most phones these days are sold as dual-band or tri-band phones. If you've bought your phone from the UK the chances are that your phone will work anywhere in Europe, Africa or Asia (a dual-band phone). AND maybe even the US and Canada (tri-band phone). If you are experiencing difficulties ordering online please contact us via email or telephone customer support on 0870 600 1362. Our lines are open 24/7 and someone will get back with you during regular working hours to take your order.

These terms define the working frequencies of GSM cellular phones on particular networks. There are 3 working frequencies - 900/1800/1900. GSM phones that work on 2 frequencies are called dual band while those that work on 3 frequencies are called tri-band. This facility allows the user to use his/her cell on different networks, and beneficial for international roaming.

Dual band phones tend to work in the UK and Europe and most of the world (GSM 1800 and GSM 900), whilst in America you need a phone that can take GSM 1900 so most often a Tri band or Quad band phone is the best option.

The Vodafone Datacard is a quad-band card GSM 850/900/1800/1900. The Vodafone USB Modem is Tri-band GSM 900/1800/1900.

You can get a dual band antenna that will cover all 3 modes (analog, digital cellular and digital pcs) or, as mentioned above, focus on where you're having reception problems. First find out what network your phone is actually using in your city by calling your service provider. Just ask if you're in a 800MHz range area or 1900MHz range area.

GSM Mobile Technology operates on three frequency levels - 900 MHz, 1800 MHz and 1900MHz. Dual band means that your phone will work on 900 MHz and 1800 MHzfrequency levels. Tri-band means that your phone will work on all three levels, for example if you're traveling to the USA and plan to use your phone, you would need a tri-band phone as they operate on 1900 MHz levels. All of our phones are dual band so you can still enjoy a great variety of top class phones for every budget.

GSM Mobile Technology operates in Antigua on one frequency level - 900 MHz. Dual band means that your phone will work on 900 MHz and 1800 MHz frequency levels. Tri-band means that your phone will work on 900 MHz, 1800 MHz and 1900 MHz frequency levels, for example if you're traveling to the USA and plan to use your phone, you would need a tri-band phone as they operate on 1900 MHz levels.

Dual band refers to cellular telephones that are able to operate on two different frequency bands, such as GSM 900 and GSM 1900. If a phone has dual band capability, it automatically scans for the strongest signal and switches Networks â?" even during a call within the same operator's Network.

TRI stands for Trisomy 21 Research Foundation, Inc., a non-profit organization founded by Dr. Lawrence Leichtman to further investigate TNI as a therapeutic treatment for patients with Down syndrome and encourage further research.

Tri band refers to the physical frequencies which your mobile phone can operate on. The three international frequencies ranges or bands reserved for GSM are 900MHz, 1800MHz and 1900MHz. A Tri Band phone is what you will need to use in the US. They use GSM 1900 there, just to be different (for a change).

A Tri-band phone is a phone that operates on three frequency bands, for example, Global System for Mobile communication (GSM) 900MHz, GSM 1800MHz, and GSM 1900MHz. A GSM tri-band phone can be widely used in Europe, Africa, Asia, North America, and Australia, because the same phone can be used on different networks using different frequency bands.

Dual band refers to the radio frequencies which your mobile phone can operate on. The three international frequencies ranges or bands reserved for GSM are 900MHz, 1800MHz and 1900MHz. In the Uk, Orange, One to One, Virgin and Telecom Plus use GSM 1800: Cellnet and Vodafone use GSM 900.

It is peripheral specific. For example thru a USB peripheral it is Quad-band and thru Compact Flash it is Tri-band.

The USB Modem is tri-band which means it supports the 900/1800/1900 MHz GSM network frequencies. Quad-band devices also support the 850 MHz network frequency. This means that in a small number of countries - mainly in the Caribbean - the device may not work.

Tri EndoLean should be taken twice per day before the first meal and lunch. Begin by taking one capsule with Breakfast for three days. Once acclimated to the effect of Tri EndoLean, one capsule should be taken with Breakfast and one before Lunch. After another three days, you can increase the dosage to 2 capsules with breakfast and 2 capsules with lunch. If at any time the user experiences insomnia, the second dose in the day should be reduced from 2 capsules back to one capsule.

Some VHF/UHF rigs are capable of acting as a cross-band repeater, operated by carrier-sense. Unless these are licensed as a repeater (with a GB3. call sign) or being operating by an emergency communications group under a current 'talk-though' permit then they may not be used as a repeater. This is a case of Radio Frequency Interference and the correct term is 'Electromagnetic Compatibility' or EMC.

Before PCS, all cell phones were single band devices that operated only in the Cellar 800 band. When service providers started to deploy both Cellular band and PCS band service, the cellular phone manufacturers started to make dual-band phones. These phones constantly report the signals and channels that are receiving to the towers, even when there is no call engaged.

Simply put, dual-band boosters sound more appealing. From the user's point of view, It seems that you get more for the same price. From the seller's point of view it is an easier sell, the consumer is easier to sell and the seller does not have to assess which phone, coverage area, service provider or any other technical information to recommend the correct device to the consumer.

Dual-band/dual-mode phones are also known as tri-mode phones. They can operate in digital mode on 800 MHz and 1900 MHz. The phones can also operate in analog mode on 800 MHz. What this means is that the phones can operate on the three major wireless systems deployed in the U.S., thereby allowing your phone to work almost anywhere wireless coverage exists in the United States.

Working Assets Wireless customers enjoy the best wireless coverage available through Sprint, providing the largest all-digital, all-PCS nationwide network. The network covers more than 4,000 metropolitan areas and communities across the country. Digital technology allows your call to be processed and carried on the network more efficiently than an analog network. Digital technology also ensures greater call security than analog technology.

A booster is a radio frequency amplifier that will do two things: it will take the signal that is transmitted by the cell phone when a call is engaged and use electrical energy to make it stronger and send it out through the antenna to the tower. The booster will also receive the signal that was generated by the tower, through the booster antenna, use electrical energy to amplify the tower signal and send it to the phone.

Even though it would seem that a dual band booster is better than a single band booster, after all, this device will amplify all the time, there are valid reasons that a dual band booster is not better than a single band booster and will almost always have inferior performance and practical reasons that it is not needed.

Tri band refers to the physical frequencies which your mobile phone can operate on. The three international frequencies ranges or bands reserved for GSM are 900MHz, 1800MHz and 1900MHz. In Australia, as at the time of publication, most GSM networks still use only the 900MHz frequency band. Soon, GSM carriers will be upgrading their networks to support the 1800MHz band also.

MTNL's Broadband service is called as "Tri-Band". This is based on ADSL 2+ technology which is the most advanced technology in the world.

Dual band refers to the radio frequencies which your mobile phone can operate on. The three international frequencies ranges or bands reserved for GSM are 900MHz, 1800MHz and 1900MHz. In Australia, most GSM networks use the 900MHz frequency band although some networks are now using the 1800MHz frequency band also.

The JDTECK Dual Band Booster is a linier amplifier that amplifies both transmit and receive signals in the (824-849 / 869-896 & 1850-1910 / 1930-1990) frequency band. The actual mode of transportation used (CDMA / TDMA / GSM / GPRS / PCS / AMPS) is irrelevant with our amplifier.