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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)
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!
Switching was a royal pain in the ass, since they had totally replicated everything staffing-wise and billing-wise and all that, for the new network, and at that point, folks still weren't very clear on where to forward existing customers who wanted to switch. Eventually, though, I got a nice shiny Nokia 3650 (at no small expense).
At that point in time, I was told up front that GSM was pretty much available only in and around the biggest town in the area (where, conveniently, I live), and that service would be coming soon further out (where TDMA service already was, and had been, available). Okay, no problem.
10 months passed. I noticed that there my coverage wasn't nearly as good as it had been. More than about 10 miles from town in any direction and I had no service. I went for a long bike ride, spent 7 hours incommunicado, and my wife was calling hospitals to see if my body had been brought in.
Why did all this happen? Simple. The Nokia 3650 is a 900/1800/1900MHz "World Phone." Here in town, ATT's tower has GSM on 850/1900MHz... everywhere outside town it's 850MHz only. Whoops, ATT.
Oh, and of course you can go to any ATT kiosk or store in town and buy a 3650 to this day. The new 3620 (850/1900MHz, yay!) isn't yet available in stores... but it will be, soon... I hope...
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)
Nice to see that us Europeans do some things better than our US cousins ;-)
The best book I ever read
That's just bs... All you have to do is buy a cellphone that isn't locked to a certain carrier, and that handles the GSM-band of the countries you're planing on visiting, and then either roam or buy a local SIM-card.
I've been roaming within europe since mid 90's, and I've used tri-band phone in europe and the us since late 90's; no problems at all.
perl -e'print$_{$_} for sort%_=`lynx -dump svanstrom.com/t`'
however, as I've seen in the US none of the mobile phones actually have a removable SIMcard
My Sony-Ericcson T616, bought from AT&T Wireless, has a SIM card. In fact, I've never seen a US-sold GSM phone *without* a SIM card.
Maybe you're thinking of older CMDA/TMDA phones.
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
Well I bought a Nokia 8890 in the US about 4 years ago, it has a removable SIM card and I am happily using it in the UK.
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
We chose the Motorola V66 phones because of their triband functionality.
After activating the TMobile Worldclass service (free to activate) I have traveled to Europe without a problem. I switch to the local band, and I'm on in most cases. Only once have I had to call local customer service.
There is a list available online. I do know that my triband does NOT work in Japan. But you can actually rent a phone from Tmobile if needs be. Since you mentioned Japan as a destination, this might present a problem for you.
----- 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.
Actually, any carrier in the US (world) that uses the GSM spectra, either in the 800, 850, 1800, or 1900 MHz bands have to use the SIM cards. To my knowledge, those carriers include, but are not limited to:
Cingular
AT&T Wireless
T-Mobile
Nextel (the original walkie-talkie cellphone people) has been using SIM chips in the last two generations of their phones, the i35sx thru i95cl (now being phased out) and the newer, 'Condor-series' phones, the i205 thru the i730; but, these phones do not work on *any* GSM spectra, they work on the propietary iDEN network made by Motorola.
Sprint is a PCS provider. I'm unaware of any international PCS provider, either in existance, or that is compatible with Sprint PCS.
Verizon is currently CDMA 1xRTT, which is incompatible with GSM. They also do not utilize SIM chips in their handsets.
As I walk through the valley of death I fear no one, for I am the meanest sonova bitch in the valley!
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
It is more productive to voice thoughtful opinions (reply) than to judge (moderate) others.
Sorry, a bit more reading makes it look like AT&T's "GSM 850" is really a replacement of their analog 850MHz but running on 800MHz.
... to get AT&T's converted area (and AT&T also runs on one of the standard bands for their first round of PCS/GSM service, they're just converting their analog towers to GSM on a different freq) you'd need 800 / 900 / 1800 / 1900 ... ie a quadband phone. I doubt that any of the non-AT&T phones will support GSM 800 right now and not all of AT&T's phones do either.
The T610 should be a GSM 900 / 1800 / 1900
It is more productive to voice thoughtful opinions (reply) than to judge (moderate) others.
In some places, it easy to get hold os a pay as you go SIM. However, with the usual crap about terrorism/drug dealers/insert bogeyman of choice, it is very difficult in many countries to buy a SIM card without having proof of legal residence in the country where you are visiting. For someone coming from the US to say, Germany and living out of a hotel, this would not be possible. The workaround is to ask the host organisation to organise a SIM in their name. Not possible for tourists but businessmen can try this one. I believe that the UK will still allow you to buy a pay as you go SIM without a postal address.
See my journal, I write things there
from what I have read, t-mobile will make you wait until you've had service for 90 days before they'll do this. (I think you also need to be paid up)
Why do you want pre-paid for a few weeks? I'm sure it makes sense, for some, but why? Personally I'd tell my friends to only call in emergency's, and use my Tmobile sim over there. Sure you pay roaming, way to much, but you also get one number that you can give everyone, and can always be reached in emergencies. Use the hotel phone.
If you really will make a lot of calls over there, to others over there, pick up a prepaid phone there, they are cheap enough.
BTW, while you are at it, call your carrier and complain that roaming in Europe is so high. It is all accounting, they can do whatever they want (Okay, I know those undersea cables cost money) with the billing. And get your friends in Europe to complain too. Perhaps someday we can do something about it.
Nah, just tell them you are going on a trip, they did it for me in under 30.
Slight correction....
PCS is the name that Sprint operates under and the name for the 1900 MHz band that they operate in.
Sprint PCS is CDMA 1xRTT or CdmaOne (the slower, 2G predecessor to 1xRTT) like Verizon.
But you are right in that neither the CDMA (IS-95) nor the TDMA (IS-136) standards include the notion of a SIM card in the standard, so nobody has one.
Gentoo Sucks
Both GSM and CDMA are useless in Japan. NTT Docomo uses a different proprietary protocol.
-molo
Using your sig line to advertise for friends is lame.
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.
On a related note... I was shopping for new phones recently and had two sales people tell me that an unlocked phone will lead to more roaming charges since it will auto-switch over to another provider's network if the signal is better. Is there any truth to this?
Ouch! The truth hurts!
PCS service is available in several countries, besides the US. I'm in Canada with a local PCS provider that has roaming agreements with US carriers (Sprint in particular, I think, or at least it used to be Sprint.)
Other countries in which my PCS phone provides PCS servies include Hong Kong, Mexico, Bermuda, Dominican Republic, etc...
As an aside, I designed one of the digital baseband circuit boards in a particular model of those Sprint PCS basestations.
Dave
FPGA, Wireless, ASIC, Verilog, VHDL, HW, 10yr exp, Team Lead, Ottawa (More? Email above. slashdotusername=dgmartin98 )
T-Mob's phone are locked so that you can't put another company's SIM card in the phone, but you can find sites on the internet with instructions to unlock phones (I leave locating the sites as an exercise for the reader) . . . or many third party phone shops will do it for you, but they can charge as much as $30-$40. I unlocked my phone the day I got it and I never had any problems with the phone accidentally connecting to another GSM network while I was the standard area of my calling plan (as someone else on /. said may happen with an unlocked phone). However, I suppose if this should happen it should be EZ to correct because when I'm roaming, the phone allows me to scan for other networks and select the one that I want to connect to (I suppose I could reconnect to my home network if this ever happened).
Note that changing SIM cards changes your phone number. I use my phone for business so I can't afford be swapping numbers (unless I'm on vacation or something like that) . . . but normally, I hangup and call immediately on a landline to save on the expensive (USD$1 - $2) overseas roaming fees. I also really dig being able to get/send text messages on the phone . . . however, As a US T-Mobile customer, I have had significant difficulty getting and sending text msgs to/from people using European mobile phone providers. This happens even if I'm in the same country and roaming on the same service. Though you may be considering buying a phone in your destination country and chucking it later, that's a lot of money (if you get a nice phone, the cost of 2 nice phone can easily exceed a triband and when you include chargers, that can be a lot of extra junk to carry around while traveling.)
Note that GSM phones do NOT work in Japan (they have their own standard. You can get a Japan friendly phone that also supports GSM tri-band (So that it will work inside and outside of Japan, but I think it's hard to find these phones outside of Japan).
Also, from my experience, all of the the GSM phones from ATT have SIM cards that you can swap freely (if the phone is unlocked). Most U.S. carriers' phones have removable SIM cards (except some legacy types, those aren't world phones anyway...).
My apologies, corrections noted. Hopefully same mistake won't be made again (also being as I just picked up Sprint service today).
As I walk through the valley of death I fear no one, for I am the meanest sonova bitch in the valley!
the t616 does have a sim card.
the t616 and t610 are basically the exact same phone, except the frequencies they operate on. the t616, sold only by at&t and maybe cingular is 850/1800/1900. whereas the t610 is 900/1800/1900
Before anybody tells you different, if you buy a World Phone with a contract from Cingular (Ericsson T616, Motorola V400) they are now UNLOCKED so you can use a sim card from any GSM provider directly.
Cool, huh?
Do you know if AT&T has roaming agreements on GSM850 for other carriers? I might give my wife my T610 (she needs it at work where GSM900 works fine) if I can find a 850/900/1800/1900 phone so I can use it from home.
It is more productive to voice thoughtful opinions (reply) than to judge (moderate) others.