Swapping SIM cards and second lines

Q: Cingular told me that my AT&T Wireless SIM card won't work in a new Cingular Motorola Slvr. What the heck? I thought moving the SIM easily was the whole idea behind SIM card technology. Is there no way I can use the phone list off my old card?
—Jack

A: SIM card technology does allow you to switch cards from one GSM cell phone to another, but only when the phones in question were activated by the same carrier or are unlocked so that their settings aren't tied to any one carrier. And although AT&T and Cingular have merged, old AT&T SIM cards like yours will not work in a new Cingular phone like the Slvr. No, this policy doesn't make a lot of sense--unless you consider that it's Cingular's way to move all former AT&T customers onto new Cingular contracts.

There is an out, though. If you're intent on keeping your AT&T SIM card and using a Slvr, you can always buy an unlocked Slvr, and you'll be all set to make calls as normal. You can find an unlocked Slvr online or in cell phone stores that aren't affiliated with a carrier.

Q: Is there a way to get two phone lines assigned to one handset? I'd like to use the same phone for personal and work calls.
—Lourdes

A: Nextel offers a second-line service on handsets like the Motorola i580. The handy service allows you to add a second line with a different phone number to a phone--perfect for anyone who wants separate digits for personal and business use. Nextel was one of the first U.S. carriers to offer the functionality. You'll need to sign up for a second service plan, but you can have separate ring tones, separate billing statements, and even phone numbers with different area codes. Hopefully, we'll see this service from other carriers soon.

Q: I have a Verizon Wireless LG VX8100. I'm traveling to Belgium and Spain soon, and I want to use a cell phone while there. I've talked to Verizon about renting a GSM Nokia phone, but at $3 to $5 per day and $1.49 per minute for voice calls, it's quite expensive. Is that the standard way to handle travel to Europe, should I just buy/rent over there, or switch to Cingular/T-Mobile here?
—George

A: You can rent a phone from Verizon (it will have the same phone number as your VX8100) but as you say, that option is quite pricey, particularly if you think you'll be making a lot of calls while abroad. It can also be quite a hassle to go through the rental process, and the Nokia that you'll rent will likely be a low-end, basic phone.

You're correct that another switching to T-Mobile or Cingular is another option, but their international roaming rates can be just as expensive. Sure, you won't have to pay to rent on an additional phone, but if it means you'll have to break your Verizon contract and pay a fee, you should consider the costs carefully. Plus, if you're happy with Verizon, it's probably not worth it to switch to another carrier for this one trip.

Your third and probably your best option is to buy an unlocked GSM phone (the cheapest sell for around $100), then use prepaid SIM cards in the countries to which you're traveling. You'll have to pay the cost of the phone up front, but you'll save a lot in terms of roaming rates. The only drawback with this option is that you'll have Belgian and Spanish phone numbers while you travel in those countries. That's fine for making calls in those countries, but if you plan on calling the United States frequently, you'll pay for international dialing. For more information, please see CNET's quick guide to world phones.

Q: I am interested in buying a GSM unlocked phone but am hesitant to buy one that doesn't have both the 850 and 1900 GSM bands. I know that only 1900 is needed to work on most networks, but how important is it to have 850 as well? I am looking specifically at a Samsung phone and want to use it with T-Mobile.
—Ben

A: As you must know, Ben, 850 and 1900 bands are the two GSM bands used in the United States. I usually recommend using a phone that supports both bands because it will give you the most comprehensive coverage. However, you can get by with just the 1900 band and have little trouble placing and receiving calls. Just keep in mind that your coverage will be spottier inside buildings and in rural areas.