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GSM Phone Usage


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General GSM Information

What is GSM?
GSM (Global System for Mobile Communications) is the world's predominant mobile phone standard, first adopted in Europe and then quickly spreading throughout Asia, Africa and the Pacific Rim (Australia, N. Zealand, etc.). GSM enables the same cell phone to work in London, Johannesburg, Beijing, Sydney and elsewhere.

The United States however, did not standardize GSM as a part of it's infrastructure, instead leaving the development of cellular service to competing wire carriers which created whatever standard they wished including CDMA and TDMA. Only recently has the US aggressively embraced the GSM standard, which makes the Cellular Abroad service that much better.

Carriers such as T-Mobile, Cingular and AT&T are now providing GSM service in the majority of the markets they serve. However, the GSM standard that we use in the US and Canada is not always compatible overseas. This explains why many US travelers have difficulty getting wireless coverage overseas without paying $1-$7/minute and why you should consult with the experts here at Cellular Abroad.

What is a SIM card?
The SIM (Subscriber Identity Module) card also known as a "smart chip" is basically the "brain" of the phone, providing cellular service as well as many other functions including call log, voice mail and SMS and GPRS (internet connection standards). SIM cards are the size of a credit card but they have a pop-out chip about the size of a postage stamp which fits into all modern GSM phones. The smart chip is embedded with circuitry and when inserted into a GSM mobile phone provides wireless phone service on a particular GSM network. SIM cards are usually available prepaid or on a contractual basis, however Cellular Abroad only offers the prepaid version which is the most popular because of the user's complete control over how much they spend. There are no hidden fees or surprise charges. To see what a SIM card looks like, click here for our visual guide.

Is this like a calling card?
Not really. You cannot receive a call with a calling card. Calling cards are a bit risky and often provide poor customer service. With the increasing popularity of mobile phones, it is not uncommon to find broken pay phones that go unrepaired by companies that own them.

I currently have a GSM Phone. Will it work overseas?
It is possible, though unlikely, that your current US GSM cell phone will work overseas. Most GSM phones sold in the US are only compatible with the nation-wide operating frequency of 1900 MHz (or the emerging 850MHz band). Overseas services use 900 and/or 1800 MHz frequency standards, which is why we carry only (unlocked) tri-band phones. Most carriers offer global tri-band phones, however they provide them "locked" which is a distinct disadvantage for the consumer.
All GSM cell phones sold through Cellular Abroad are unlocked and ready to use on practically all GSM networks and with all SIM cards. At Cellular Abroad we believe in freedom of choice for our customers in order to provide the best possible price on airtime and network service. Most other plans force you to use one system with no control over airtime pricing nor the lowest rates available.

What is a locked cell phone?
A locked cell phone is one that has been altered in order to use only one particular cellular network. This is often referred to as a service provider lock or "SP lock" for short. All GSM network operators lock the GSM cell phones they sell or offer with their cellular services. This is the hidden cost of the otherwise "free" or heavily-discounted phone you might receive directly from a network operator by signing a service contract. The cost of providing you with a "free" or low cost phone is subsidized over time through more expensive phone rates when you make calls domestically or roaming overseas. In the end, you end up paying much more for your "free" phone and service than you would if you purchased a package through Cellular Abroad and had the rock-bottom prices available everywhere. An unlocked phone is therefore one where this software restriction has been removed.

How is the cellular coverage in other countries?
Generally speaking, cellular coverage overseas is excellent-much better than average coverage in the US and Canada. Cellular usage is more common overseas than it is in the US and the GSM standard is a higher quality than many of the technologies available domestically. One point to make, however, is that buildings in Europe are sometimes many hundreds of years old. Thus they have much thicker walls than relatively modern US architecture, so if you are indoors and away from a window, you may have difficulty getting reception.

What are PIN and PUK numbers?
Some prepaid SIM cards have a security mechanism in place that requires the subscriber to enter in a PIN (personal identification number) code every time the GSM cell phone is turned on. When a PIN code has been assigned it is important not to forget this code. If you enter the PIN code incorrectly into the phone 3 times in a row then your GSM cell phone will display a Blocked message on its LCD. When this occurs you will then be required to unblock your phone using the PUK code. If you enter the PUK phone incorrectly 10 times in a row you will block your SIM card indefinitely. All phones have a different set of procedures to unblock and you will need to consult your GSM cell phone manual when this occurs. We strongly suggest that if you have the PIN-check feature enabled on your SIM card, that you turn it off. Please consult your phone manual's index under the "security" or "lock" section if unsure how to disable PIN-check.

How do I install a SIM card?
SIM cards typically are credit-card sized cards with a smaller SIM chip almost completely floating within the card and attached on one edge of the chip by some perforated plastic. The chip is approximately the size of a standard postage stamp folded in half. You can refer to this installation animation to get an idea of how easy it is to install a SIM chip into your GSM phone.

What is Bluetooth™?
Bluetooth is a wireless technology which provides a way to connect and exchange information between devices like personal digital assistants (PDAs), mobile phones, laptops, PCs, printers and digital cameras via a secure, low-cost, globally-available short range radio frequency. Bluetooth™ cell phones also allow you to use popular wireless hands-free earpieces and wireless speaker car kits.

Cellular Abroad Questions [back to top]

Is it better to buy or rent the phones from you?
There is no simple answer for this. If your rental period approaches 2 months, you would be better off buying the phone. Also, if you travel often, it makes sense not having to keep paying for shipping. Renting a phone is a good way to try out our phone and see if you like it. If you decide to keep the rental, you pay no rental fee. You simply forfeit the deposit on the phone. On the other hand, purchasing a phone ensures you will be acquiring an unused handset.

How can I be sure the technology won't become obsolete in the future?
This certainly won't occur in the near future. In fact, this is a relatively new technology in the US that many of the cellular service providers are quickly embracing. Sure, there will always be newer, smaller and "better" cell phones introduced in the future, but the underlying technology powering the service will remain the same. Consider classic cars as an analogy; while they may be less modern, they still get you around because even the oldest vehicles use gasoline for power.

How many minutes come with the SIM card?
The SIM cards usually come with call credits measured in monetary units such as euros rather than increments of time. This is because rate charges for calls vary depending on time of day, destination of the calls and other discounts or charges the carrier may apply. Also, with most GSM carriers providing free incoming calls to the user, the number of minutes on the SIM card could be substantial without the need to add more call credits.

If the SIM card costs $80, do I get $80 worth of talk time?
When you purchase the prepaid SIM card, you are buying the brain that inserts into your GSM cell phone and makes it work. There is always some credit included with new SIM cards, but the amounts vary from country to country. Additional airtime is purchased locally and usually available at or near face value. For example, a 25 Euro voucher will credit your SIM card 25 Euros. The remaining cost for the SIM card is a set-up fee which pays for service on this particular pre-paid account.

What are the calling rates and rental and purchase prices?
Rates vary from country to country and whether you are utilizing a country-specific or international SIM card. Please check the exact rates by visiting our Prices and Rates page and selecting the name(s) of your destination country(ies). Results will display per-minute calling rates, as well as handset and SIM card rental and purchase prices. Remember, with the exception of just a few countries, incoming calls (received within-country) are FREE - regardless of origin.

How do I calculate my rental period?
It is important to remember that your phone rental is measured from the date of your stated departure until the date it is sent back (not when it arrives) or returned in person. We always ship FedEx Express 2-Day (unless faster service is required) and do our best to have the package arrive 2 business days before departure. We use FedEx tracking information to document the period of time for shipped phones. The number of days the rental is out between these two ship times minus 4 business days will be rounded up or down to the closest weekly rental period.

I live in the LA area. Can I pickup a rental or make a purchase at your offices?
Cellular Abroad operates as an Internet business, not a retail location. Walk-in sales or will-call service is possible, but a $10 service fee will be charged for this service. If you're planning on stopping in, please call ahead for directions and availability of the item you seek. It's also extremely helpful to us—if you've already made your purchase decision prior to arriving—to supply your name, billing address and other pertinent information. This will help us to expedite your purchase. Our office hours are 8 AM to 6 PM Pacific Time. During our winter low-season months, we close at 5 PM.

After my trip, could I use the phone I buy from Cellular Abroad at home?
The answer to this question depends on what network you currently use and if you're planning on replacing an old phone or looking to establish a new phone plan. All of our package phones will work only on GSM networks. (The phones cannot work on Sprint, Verizon or Nextel networks.) A lot of our customers find a prepaid card from T-Mobile is a great solution for infrequent phone users or as a starter or emergency phone for children. Here in the US, our tri-band phones work on the 1900 MHz GSM band, which is the predominant GSM band in use in the U.S. (At this time, T-Mobile operates only on this frequency.) While GSM technology is the world standard for mobile phone communications, you may find that your local GSM provider has poor coverage in your area. We at Cellular Abroad cannot determine this information for you. Your best bet is to ask people you know who use a local GSM carrier what what their experience has been. Another possibililty is that part of your local provider's network may be setup on the 850 MHz band. (Cingular uses the 850 MHz band in some areas.) If this is the case in your area and you want to buy a phone for use in the US as well as abroad, you may want to invest in a quad-band phone. You will also want to check directly with the desired GSM carrier to find out their rate plans. Ask a service rep about the phone model you intend on purchasing and what's involved in integrating that phone with their service. If you are told that the phone is not supported, this will mean either that they do not have service reps trained on that model phone or that you will need a quad-band phone to give you coverage in areas serviced by the 850 MHz network.

GSM Phone Usage [back to top]

Will my phone come with a charger?
Yes! All of our cell phones (for rent or for sale) come with a variable-voltage travel charger plus wall-plug adapters for overseas. Our rental phones are shipped pre-charged.

What is my new cell phone number?
Your new cell phone number is a local number for the country pertaining to your SIM card. For example, if you have an Italian SIM card, your number will be a local Italian cell phone number.

Can somebody else use my SIM card?
Anyone can use your card. If you lose your phone with the SIM card inside, you can usually call customer service to deactivate the card so that nobody can use the remaining credit, though they won't be able to issue you a new card. You can also safely lend your phone and SIM card to friends without worrying about incurring any out-of-pocket costs. If they need more talk time, they can simply add some by purchasing a recharge card and using it with your SIM card.

Can I retain my US cellular phone number?
Unfortunately you cannot. We recommend that you leave your overseas cellular number on your domestic voice mail. This way, whoever needs to reach you while you are overseas can still do so. You might be able to forward calls, providing someone can program forwarding for you back in the States. The problem with this is that all wrong numbers, telemarketers and everyone else you don't want to hear from when you're abroad will be able to reach you and that will end up being a nuisance.

Will I have voicemail?
Most GSM phones have voicemail capacity, but it depends on what services are available through the local provider. In almost all cases voicemail is included with your service.

What about email and internet (SMS, WiFi, GPRS)?
These options depend on the local service provider and the hardware (phone handset) being used. Almost all GSM providers support SMS (Short Message Service or "text messaging"). And in countries where incoming calls are free, incoming SMS messages tend to be free. A general rule of thumb is that SMS rates are usually about half the cost of an outgoing per-minute rate, whether local or international.

GPRS-enabled phones can access the internet when used with the SIM card from a carrier that offers that service. Rates and configuration are obtained through the carrier and can vary widely. Some GPRS phones can be used as a modem when connected to a laptop computer. Again, rates and services offered vary and are determined by the carrier whose SIM is being used in the phone at the time.

For full connectivity, a laptop computer with a WiFi access card will work in some destinations. Wireless access is becoming more prevalent in all countries, though accessing it will vary depending on the terms of the service provider. A great book on the subject is "Global Mobile - Connecting without Walls, Wires or Borders" by Fred Johnson.

For simple email Cellular Abroad offers the Email Abroad. It's unique little Composer isn't much larger than a phone and stores outgoing email that you compose when you want to record memories of sightseeing from a sidewalk café, for example. To send outgoing emails and download incoming emails, simply dial a local access number from any phone, hold the device to the phone and the messages are sent. It's cheap, light and has a calendar and other organizational features.

Additionally, internet cafes and terminals are not hard to find almost everywhere. We've seen coin operated terminals in beachside convenience stores and an internet café in the Andes Mountains of Colombia. These are great for logging on to the internet to check emails and catch up on the news or to research the next destination. Rates are often only a few dollars an hour.

Can I use multiple SIM cards with my phone?
Since we offer only unlocked phones, you can swap SIM cards as often as you like. However if you are traveling to multiple countries, you might consider that each SIM card has its own unique phone number. In the case of traveling to many countries during one trip, an International SIM card is the optimal choice for many travelers as you keep the same phone number regardless of your position on the globe. Note that you will be roaming when outside the country of origin for the card.

If I run out of call credit, do I buy another SIM card?
NO! Remember, the SIM card is the "brains" of your phone and is rechargeable. Once you have a SIM card all you need to do is add credit for more talk time. Make sure that you do not wait beyond the service life of your SIM card to add more call credit.

How do I add more "talk time" to my SIM card?
In prepaid phone lingo, adding more talk time is known as "recharging" or "topping-up" a SIM card. Recharging a SIM card is as easy as entering a code number into the handset. Recharge voucher cards with recharge codes on them can be purchased at many convenience stores, magazine kiosks and cell phone stores. They are also often found at post offices, train stations and airports. Please note that you can only purchase recharge cards within the country of origin. (If you have a country-specific SIM for Germany, for instance, you can only purchase recharge cards for that SIM card within Germany.)

Will my country-specific SIM card work outside the country of origin?
When you use a country-specific SIM card outside of its home country, this is known as "roaming". While this is often possible to do, there are some problems that make this undesirable for longer side-trips. First of all, the rates are much more expensive for making local and international calls and you don't get free incoming calls. Also, if you run out of credit, you rarely can purchase recharge vouchers outside of the country of origin.

How do I roam with my country-specific SIM card?
First of all, Cellular Abroad does not support roaming out-of-country with country-specific SIM cards. (There are too many possibilities and variables for us to do this adequately.) That said, here are some rules-of-thumb for you to use if you plan to roam:

  1. Call customer service for your SIM card carrier to request or confirm that your SIM has roaming capabilities enabled. Roaming with some SIM cards may NOT be possible at all.
  2. Make sure to ask customer service if there are any variations in dialing to or from your number when roaming. (Perhaps the use of a different country code or dialing prefix, etc.)
  3. Ask customer service to provide dialing rates for making and receiving calls when roaming for all scenarios of interest. (Customer service may not be available from the U.S.)
  4. Make sure you have a good guesstimate of how much time you'll use the phone when roaming.
  5. Buy and apply adequate call credits (via recharge vouchers) for use when roaming. You may want to purchase a "backup" recharge voucher to use in case your SIM card runs out of call credits when you are roaming.

How do I know how much call credit I have remaining?
You can always check your remaining call credit. The instructions vary from country to country and are always provided with the SIM cards you purchase through us. They can also be found at the bottom of the Customer Service page. Typically you either call a special number or send an SMS message and the carrier answers back with your remaining credit.

What's a "Service Life" ?
Prepaid calling plans provide users with the easiest commitment-free way to obtain a cellular phone number. For obvious reasons, service providers only have a limited quantity of phone numbers to distribute and it only makes sense to diable an account which has remained dormant for a reasonable amount of time. Most carriers refer to a service life as the time from activation (or recharge) of the prepaid account to a pre-designated cut-off time whereby there has been no additional recharge credit applied to the prepaid account. (Account activation usually takes place at the time of the first outgoing call.) Different carriers take different actions at the end of the service life. Most choose to decommission the SIM card, effectively disassociating the phone number from the SIM. Afterwards, the customer may be able to reactivate the account but will need to obtain a new number. Many services simply force the customer to obtain a new SIM card if the service life has lapsed. As long as regular recharge credits are being applied to the prepaid account (within the service life period), you should be able to keep the account active and retain the phone number associated with the account.

Troubleshooting [back to top]

I am currently overseas and I charged the phone and inserted the SIM card, but I still can't make any calls. What's wrong?
Generally this problem can be rectified by changing the band the phone is currently operating on. For example, if you are in Europe and the band of your GSM cell phone is set to the 1900 frequency, you will need to reset it to the 900/1800 frequency for it to work properly. Usually you'll know you're using the incorrect frequency if you do not a get a signal on the LCD display of your cell phone. However this is not always the case as it could also mean you are simply not in a good coverage area or indoors. Many European buildings have thicker walls than in the US, so your phone may not work if you are not near a window. If you are roaming and your carrier has different roaming agreements with other carriers, you may be able to improve your coverage by manually switching GSM networks. For details on how to do this, consult your manual.

What if my cell phone or SIM card doesn't work?
It is rare that one of our cell phones wouldn't work and extremely rare for a SIM card not to work. We personally test all of our phones prior to sending them out to ensure quality service and no defects. You can double-check this after you receive your cell phone and a SIM card for your overseas trip. Simply charge the phone and then see if it powers on. While you can't use the foreign SIM card here in the U.S., if your phone powers on (after you have charged it), it should work fine. Less than 1% of all GSM cellular phones are defective and less than 1 in 10,000 SIM cards are defective. If for some reason a phone or SIM card purchased from Cellular Abroad proves defective, it will be replaced ASAP. If you encounter problems while on the road, you will first want to determine if the problem is a network problem or if it is hardware-related. If you can use someone else's GSM phone and reproduce the problem, then you should contact customer service for the local carrier to see if there is a problem with the network. If the problem seems to be with the handset, please contact Cellular Abroad by phone at 00-1-310-862-7100 or email us at support@cellularabroad.com. Our office hours are daily from 8 AM to 5 PM Pacific Time. We will be glad to return the call to save you money while troubleshooting your issue.

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