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How (and how well) do Wireless "Worldphones" Work?
Milo_Mindbender asks: "I've seen a number of new phones (like the Sony T616) advertised as 'worldphones' that handle three or four GSM bands. As someone who travels to Japan and Europe occasionally I'm wondering how (and how well) these actually work. Can you get a temporary or prepaid SIM with a local carrier and just swap it or are the US carriers 'service locking' phones so you have to do international roaming with them even in foreign countries?"
all mobile phones in europe have a removable SIM card that allows you to change your operator as easy as swapping the sim-card (which is basically a small chipcard).
Most new phones are locked and will only accept the operators' simcards, however it is common that after one or two years you can 'unlock' your phone either for free or for a small amount so any sim-card can be used in that phone. This will allow you to buy a pre-paid SIMcard in any country in europe and use it in your phone without any administrative changes needed.
however, as I've seen in the US none of the mobile phones actually have a removable SIMcard, therefore you are tied to your current operator... talk about monopolizing mobile phone markets? there ya go... you are unable to purchase a genuine european phone and use it in the US. protest at your local senator.
To roam, you need two things. Hardware that works in the area you're using it in - if GSM, there are 3 frequency bands and a lot of new handsets support all of them.
You next need a phone company to service you - if in a foreign country this means either your service provider has a roaming agreement with a foreign service provider, or you stick a new SIM in the phone from a new service provider.
the latter option will change your phone number.
Fairly simple, really - just ask your phone company.
Second, if you buy the phone from the carrier, it will be locked and will not allow you to use a SIM card from another carrier. However, you can usually get the unlock code after you have had the phone awhile - T-mobile has been known to give out the unlock codes after 90 days.
You could also buy an unlocked phone from an independent dealer, but understand that this will cost significantly more. Unlocked phones *will* work with US carrier SIMs.
Jeff
Before this gets out of hand, most of the US is not on GSM. Two issues here:
* the frequency bands allocated (the 4 bands supported by these GSM phones) and
* the encoding (GSM, CDMA, TDMA)
GSM is gaussian shift keying (overlapping gaussian shaped pulses)
CDMA is code-division mux'ing (using the real & imaginary parts of the signal as bits)
TDMA is time-division mux'ing (splitting up the signals into time slots)
This is a dupe. We get this every two months; I'll let you do the search to grab the links for each.
What I post every time when this question comes up:
1. Get a cheap cell phone that works in the local area that you go to.
2. Get a temporary SIM card at your local 7-11.
World phones are overpriced both in initial cost and service. Do NOT proceed.
Enjoy!
CDMA networks (like Sprint and Verizon)
GSM/GPRS networks (like T-Mobile and Cingular)
Nort America Coverage Map
Typical US markets are a mix of the following: (800=800 MHz; 1900=1900 MHz)
800 AMPS
800 TDMA
800 CDMA (verizon)
800 iDen (nextel)
1900 CDMA (sprint pcs)
1900 GSM (at&t, cingular, t-mobile)
1900 TDMA (at&t)
I got an old Motorola Timeport P7389 that is unlocked and a new Nokia 6600 which is also unlocked. They work well across networks, I travel to the Philippines, Belgium, US and Canada and I just get a prepaid SIM card whenever I change locations. I avoid international roaming for security purposes especially the Philippines where crime is rampant.
You can get your phone unlocked at a lot of places here in Toronto, you should be able to get your phone unlocked if you live at any urban place as well. If you are lucky to have a Nokia you can get a DCT4 calculator (googled "free DCT4 calculator") and unlock the phone yourself, I've done that with my Nokia 6600 and my mom's Nokia 6610 as well.
My parents get international roaming on their Sim cards when they come to Canada (safe place as it is) and use their existing cell phones (all Nokia world phones) from the Philippines, works pretty well.
Archie - CIO-for-hire
Can you get a temporary or prepaid SIM with a local carrier and just swap it or are the US carriers 'service locking' phones so you have to do international roaming with them even in foreign countries?
Yes
I travel (not as frequently as I would like) to Europe and have lately been taking a Motorola P7389 tri-band GSM phone on my travels. The phone, while not the latest model, works great. I purchased it, unlocked, on eBay for short money.
On my latest trip, I purchased a Vodaphone NL from the cell phone kiosk at Schipol airport (the Netherlands) for about 20 Euro. It came with a number that is good for at least a year, and included 5 euros of credit. To top up the service, I only had to go to any of a number of outlets wherever I was in Holland, or if I could read and write Nederlands a little better, could refill the service from the internet site. Oh yes; all incoming calls (including international ones) were free. The in-country rate was less than I pay for my contracted Alltel phone here in the states.
I had the same experience in Greece and Beligum with different carriers.
I like the GSM system because it doesn't because of the flexibility it offers. If my phone dies, I can simply remove the SIM card from it and put it in another phone. I haven't verified this, but heard while I was in Europe that the EU has mandated that all phones sold in EU countries are requried to be unlocked.
GSM is a standard throughout the world (except for the US, Iraq, Afganistan and I believe, Argentina). An excellent site for finding out about prepaid GSM services is http://www.prepaidgsm.net/,
Don't be fooled by "word phones" offered by various US carriers. These phones are locked tri-band phones that roam on European GSM networks, but which are charged at outrageous rates by the US company.
wherever I go, there I am.
Another great thing about T-Mobile is that they have the geekiest add-on service of any mobile phone company. All you can eat GPRS data transfer is $20 extra per month. So is all you can eat 802.11b Hot Spot service. Of course getting both will set you back $40 extra per month. And you have to have a $30/month or more phone plan to get the deal on GPRS. My $20/month econo plan doesn't count. However, it's sufficient for the $20 a.y.c.e Hot Spot deal.
Oh yeah...phone sound quality and coverage rocks here in Los Angeles. Of course, they are using the same network as Cingular here, so Cingular users can probably say "Oh yeah? Mine's just as good." Cingular doesn't have the geeky propellerhead extra goodness, though. ^_^
Knowledge is power. Knowledge shared is power multiplied.
In order to use your gsm sim in Japan you need a 3g w-cdma handset, some include support for european gsm 900 & 1800 such as the nokia 6650 but I haven't seen one that works in the US as well... T-Mobile and probably other us carriers have roaming agreements with J-Phone and some J-Phone handsets will accept your sim card.