Cell Phone Guide
System for Mobile Communications) is the fastest growing and most
advanced mobile technology available today. GSM phones work with
a small electronic chip called the SIM card. The SIM card holds the
phone number assigned by the service provider, your phonebook and other
registration information. GSM operates on multiple frequency bands
around the world - 900 Mhz and 1800Mhz, used in Europe, Africa, Asia,
Australia and South America ; 850 Mhz and 1900 Mhz, used in the.North
America and South America. Different service providers operate on
different frequency within the country. For example, T-mobile operates
on 1900 mhz in the USA, while Cingular operates on 1900 mhz or 850 mhz.
When selecting your cell phone make sure that you select a phone that
operates on your service provider's band.
Dual band -
Usually are phones that operate on 900 mhz or 1800 mhz. These phones
will work around the world but, will not work in North America.
Tri-band - Tri-band
phones usually include 900 mhz, 1800 mhz and 1900 mhz band. These
phones will work around the world and in the North America. These
phones will not work with service providers that only support 850 mhz
in your area.
Quad band - Quad
band phones cover all the bands - 850 mhz, 900 mhz, 1800 mhz, 1900 mhz.
Quad band phones will work all over the world with all GSM service
Unlocked GSM Phones
phones are not locked to a specific service provider.Unlocked phones
will work with any GSM service provider that is supported by the
phone's frequency band. Normally, all the phones sold by the service
providers are locked to be used with their service only. For example, a
locked phone from T-mobile wouldn't work with Cingular's service.
3G is an International Telecommunication Union (ITU) specification for
the third-generation mobile communications technology that was created
for high-speed transfer of data and multimedia content, such as video,
downloads, music and interactive games. 3G aims to increase bandwidth
up to 384 Kbps when a device is stationary or moving at pedestrian
speed, 128 Kbps in a car, and 2 Mbps in fixed applications. 3G will
work over wireless air interfaces, such as GSM, TDMA, and CDMA. The new
EDGE service was developed specifically to meet the bandwidth needs of
Enhanced Data GSM Environment (EDGE) is a faster GSM wireless service
that can deliver data at rates up to 384 Kbps on a broadband. The
standard is based on the GSM standard and uses TDMA.
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Simply known as a “cable replacement” technology, Bluetooth is a
radio-frequency standard that functions as a personal-area network
(PAN). It replaces cable-based connections, like USBs, with short-range
wireless connections. The technology can be applied between desktops
and notebook computers, handhelds, PDAs, mobile phones, camera phones,
headphones, printers, digital cameras, headsets, keyboards and computer
to call us at 847-983-4761 or e-mail us
if you need assistance in selecting a a GSM cell phone for travel.
Will a 900 mhz or 1800
phone work in the USA?
No, 900 mhz or 1800 mhz
phone will not work in the US. GSM service
providers in the US include T-mobile and Cingular. T-mobile operates
only on 1900 mhz and Cingular operates on either 850 mhz or 1900 mhz
depending on your location. Be sure to check with your local carrier to
verify which band they operate on in your coverage area.
What is a Sim Card?
A sim card is a small flat rectangle plastic that contains a microchip.
This microchip contains your phone number, your phone book, and the
necessary information for your phone to work. Sim card is provided by
your GSM service provider, such as T-mobile, AT&T or Cingular in
the USA. All sim cards look the same, but the microchip inside is
different for every GSM service provider.
can I purchase a SIM card?
You may obtain a SIM card
from your service provider such as T-mobile or Cingular. You may also
use your SIM card from your current phone if you currently have GSM
service. For overseas use, you may purchase a pre-paid SIM card from
the country your traveling to. Purchasing pre-paid SIM card from your
destination country will be much cheaper than paying roaming charges to
your US service provider.
I obtain a phone number?
You will get a phone
number along with your SIM card.
Can I use the cell
phone charger in my country?
Most cell phones come with travel chargers (100~240V) so that you can
use them around the world. However, some come with 220V chargers only
so these may require a voltage converter to use in 110V countries. We
do include plug adapters along with travel charger to enable you to use
the charger in various countries.
Does your GSM cell phone
come with any contract?
No, we only sell the phones without any contract or service plans.
Therefore, you can use the phones bought from us with your current GSM
cell phones come with an English instruction manual?
Since unlocked GSM phones
come from around the world, many times they may not include an English
manual. However, an English manual may be downloaded from the
Where can I buy an Unlocked GSM Cell Phone locally in Chicago?
We have a local shop located on the northside of Chicago, with all the selections. You can stop by at anytime during regular business hours at Bombay Electronics, 5743 Howard St, Niles, IL 60714. Call us at 847-983-4761
questions? Need more clarification? Or provide feedback.