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Cell phones > Buying guide
Understanding Cellular Technology and BandsThroughout the world, different frequencies are used to send and receive wireless calls within each country. The phone manufacturers (Nokia, Motorola, Samsung, etc…) then produce phones that will work within each countries network(s). To complicate the matter in the United States; AT&T, Verizon, T-Mobile, Sprint, and the other carriers, use one of four different technologies to transmit a call to your phone. The different technologies are known as GSM, CDMA, TDMA, and I-Den. GSM and CDMA are supported by most carriers, while I-Den and TDMA are being phased out. You can think of these technologies as operating systems for your phone.
Next Page - Analog, Digital - Does it Matter?For the average user, it’s not very important what technology is being used by which carrier. Contrary to what you hear on commercials, every carrier uses and shares the same frequencies and the differences between technologies has little effect on the quality of the calls you make and receive. The more important factor is which carrier has better service in the particular areas in which you plan to use your phone — this is usually more dependent on which carrier has more cellular towers in the areas than anything else. Information regarding cellular protocols and frequencies is more important if you already have service with a carrier and you decide to purchase a phone by itself from an independent source. All phones being used in the U.S. should accommodate the 800/850 and 1900 bands to operate in most areas well, except on the T-Mobile and SunCom networks which operate solely on the 1900 bands. The 800 and 850 bands are actually the same, so don’t be confused by the two different numbers. 850 just means that the phone is GSM-only compatible, while 800 can be a GSM, CDMA, I-Den, or TDMA compatible. Any phone which lists the 800 or 850 + 1900 band in the phone specifications will work well in the U.S., as long as it is also supported by the carriers GSM, CDMA, I-den, and TDMA networks. Note that phones that are 1900 compatible but lack the 800/850 band will operate in some areas of the U.S. but not others; major metropolitan areas in particular tend to offer better 1900-band coverage. Carrier Technology and Frequency/Band Chart
Adding a replacement phone to your current carrier, U.S. only.
Frequency Bands Used throughout the WorldU.S Bands – 800/850, 1900 (CDMA, GSM, TDMA, or I-Den), 2100 CDMA 2000/EVDO What is GSM 850GSM 850 is simply GSM technology operating in the Cellular (800 MHz 850 MHz) frequency band. Both the technology and frequency band have been around for a long time, but only in 2002 were they combined. In the U.S. prior to 2002, GSM technology only operated in the PCS (1900 MHz) frequency band. GSM 850 addresses the needs of carriers with Cellular licenses switching from other technologies to GSM. Before the existence of GSM 850, the Cellular band was commonly referred to as the 800 MHz band. 850 MHz implies a different frequency band, but this is not the case. 800 MHz and 850 MHz refer to the exact same frequency band. 850 is technically a more accurate description of the frequency range, although 800 is still common when referring to CDMA and AMPS (analog) technology. Tuesday, July 22, 2008Which firm would you go with for a two week GSM phone rental for use in Japan, with v/mail, calling to and from U.S.? Thursday, July 17, 2008Is there any plan that does not require a two year contract to start service. I have t-mobile, my contract is running out, but I am upset with the service we have had and don't want to have to commit to another two years, tho I can't seem to find a plan that works better for us
Wednesday, July 16, 2008I lost my ATT (GSM) phone and would like to buy a replacement so that I do not have to extend my existing phone plan. Because my phone is lost (fell in the bay), I cannot exchange the SIM card. Can I still buy a replacement phone with this plan? Friday, July 11, 2008this is informative1! can i have it please? Thursday, June 26, 2008Thanks for the good information on Insurance.. I thought I was the only one who thought it was nuts, but I never realized it was that bad. I think a manufacturer's warranty is good enough for me, but the Ebay idea is really smart! Tuesday, June 17, 2008This is a fantastic example of B2C ebusiness for sure i have liked it. Monday, June 16, 2008major complaint with t-mobile:
just thursday night i recieved 4 messages from monday
1 from my childs school telling me they are letting the kids out early-make sure someone is home
1 from a client waiting to see a house (i'm a realtor)
2 from banks concerning another deal
all very important-
all making me look incompetant
and this is not the first time Friday, May 30, 2008how to delete exceed of web sessions in Motorola L6 Thursday, May 22, 2008I have a Southern Linc model i355 motorola phone. I was told my sim card would not fit in a nextel phone. Is this true? Monday, May 19, 2008i have Alltel service and would like a new phone. I don't believe the AudioVox phone CDM 8910 that I have has a sim card. What can I do? Tuesday, May 13, 2008I have a account with suncom and am in need of an another phone.I like this one. How can I purchase one and how much? Don't forget to submit your entry for the "PhoneDog Days of Summer" Giveaway! Win one of over 30 of the hottest new cell phones - no registration, no spam! Just PhoneDog sharing some goodies with our visitors & loyal fans! Thanks and keep the comments coming! |
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