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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?"
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)
GPRS definitely works in Europe. It is an extension to GSM that uses free time slots to transmit packet data. It has nothing to do with making telephone calls.
One killer app with GSM is that it roams seamlessly between operators that have mutual agreements. Hence, as long as you use a reliable operator, there is no need to swap SIM cards when you travel abroad.
While in Norway last week I discovered that even GPRS roams perfectly, much to my surprise. I was able to use my cell phone for internet service through my Swedish operator, without changing any settings. Talk about mobile internet!
This is why it will take many years before GSM will lose its position as king of cell phone services - it just works, and is _reliable_ as hell. Audio quality is not optimal, but it's good enough. Data throughput is limited, at least without EDGE, but it's good enough for email, and it's _reliable_.
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
This is not true, I took my t-mobile phone to India and used a pre-paid sim there. I simply had to email sim-unlock@tmobile.com to get instructions to unlock my phone, and tell them I was going on a trip.
Guess you dont get out much then.
TMobile has pretty much always had removable sim cards. Why? Because it is one of the few cell phone companies selling in the US market with a large worldwide romaing plan. How did this come about? Because TMobile is actually an international company.
And to think you got moderated informative. Too bad there isn't a misinformative option.
----- LoboSoft specializes in Digital Language Lab
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.
If you research it it is far less restrictive, you just have to pick the right carrier.
... if it does see if it handles the GSM 850 stuff and if so call AT&T to see if they will unlock the phone for you. If AT&T matches all of those criteria, they may work better for you. Otherwise I highly recommend T-Mobile for international solutions.
... N. Ireland is part of the UK so their code is +44, not +77. That one got me for a day or so of trying to contact a friend since all they mailed was their number without the code.
I went to Ireland earlier this month and so I picked up a T-Mobile T610 and away I went. I didn't have it long enough to experiment with swapping the SIM with a prepaid, but all of T-Mobile's phones have the SIM card.
Apparently if you call 611 after having had the phone at least 2 weeks (I hadn't when I went) there are people who report online that T-Mobile will unlock your phone so that you can use a pre-paid.
I was a T-Mobile customer in the past (I had a couple years where a cellphone didn't make sense) and my wife and I both had phones. When my battery was down while we were travelling if I needed to make a call that would be billable to work I just swapped our chips for a bit.
While T-Mobile is a European company, I was a Voicestream customer before T-Mobile bought them and a Powertel customer before Voicestream bought -them- and all had SIM cards.
As for reception, the T610 worked perfectly over there. I think it is a tri-band phone so you'll get reception in GSM 800, GSM 1800 and GSM 1900 markets if I remember right. I was roaming on Vodaphone, Orange and O2 just fine. Each had their quirks (I couldn't check voicemail the normal way on one, another had to dial for awhile to connect to a WAP server instead of having an almost instant "ON") but nothing that stopped me from service. WAP worked everywhere as did SMS.
AT&T is converting their analog 850MHz to GSM, so there is another band out there that is GSM 850. I wish my T610 handled the AT&T GSM 850 frequencies since AT&T is the only carrier in my small neck of the woods. I don't know if the AT&T T616, which is basically the same phone but there are always differences, has a SIM card
Oh and a hint if anyone is going to be in Ireland and gets a phone number from someone in N. Ireland
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