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tazman556's profile

Contributor

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2 Messages

Saturday, December 14th, 2013 9:18 PM

GSM Frequencies

Does ATT support GSM 900 and 1800 MHz frequencies?

 

I'm trying to get a GSM 2G alarm system set up and don't show any bars at all, no matter where I place the main unit. I put the SIM in my GoPhone as a test. That SIM works fine in my GoPhone, 5 bars too.

 

The other possibility is obvious if the frequencies are OK.

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Guru

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349 Messages

10 years ago

Hi tazman,

 

AT&T uses different frequencies with different technologies. In some areas, they may not have a license to use both frequencies and use one exclusively. 

For GSM, they use 850 MHz and 1900 MHz. 
For HSPA+, they use 850 MHz (Band V) and 1900  MHz (Band II)
For LTE, they use 700 MHz (Band XVII) and some 1700 MHz (Band IV)

 

In your case, you'd be concerned with their GSM network. Which does not support the 900 Mhz frequency but does support the 1900 MHz band.

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Official Solution

ACE - Expert

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6.6K Messages

10 years ago


@tazman556 wrote:

Does ATT support GSM 900 and 1800 MHz frequencies?

 

I'm trying to get a GSM 2G alarm system set up and don't show any bars at all, no matter where I place the main unit. I put the SIM in my GoPhone as a test. That SIM works fine in my GoPhone, 5 bars too.

 

The other possibility is obvious if the frequencies are OK.


Neither 900 nor 1800MHz frequencies are used in the US by any of the GSM operators. As

@julywashere explained, US operators are on 850 and 1900MHz frequencies.

Contributor

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2 Messages

10 years ago

Also, this system is 2G only.

Contributor

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1 Message

10 years ago

Hi,

 

I'm planning to buy Galaxy Note 3 globally unlocked version. In the product description I've seen following line:

  • 3G: HSDPA 850 / 900 / 1900 / 2100

Does this mean that it will work fine with AT&T 3G?

ACE - Expert

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6.6K Messages

10 years ago


@sribasu wrote:

Hi,

 

I'm planning to buy Galaxy Note 3 globally unlocked version. In the product description I've seen following line:

  • 3G: HSDPA 850 / 900 / 1900 / 2100

Does this mean that it will work fine with AT&T 3G?


Yes, that means it'll work on the HSPA+ network. It may not work on the LTE network.

Contributor

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1 Message

9 years ago

Hi,

I am looking to buy an unlocked modem like this, but not sure if it works in ATT network. It is unlock. It does support 850/1900mhz, but the spec said these frequencies are only for GSM and GPRS.

 

Vodafone K5150 (also K5150H) is a new 4G LTE Cat4 USB Stick from HUAWEI to support maximum download speed to 150Mbps and upload speed to 50Mbps. The HUAWEI K5150 supports LTE band 1, band 3, band 7 and band 20(800/1800/2100/2600MHz). Like its predecessor HUAWEI K5005, the unlocked K5150 Vodafone internet stick could also support 3G UMTS/DC-HSPA+ & 2G GRPS/GSM network.

Specifications:
* 4G LTE FDD Band 1/3/7/20: 800/1800/2100/2600MHz
* 3G DC-HSPA+/UMTS/WCDMA 900/2100MHz
* GSM/GPRS 850/900/1800/1900MHz

 

Thanks,

Justin

ACE - Expert

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6.6K Messages

9 years ago


@jzforty wrote:

Hi,

I am looking to buy an unlocked modem like this, but not sure if it works in ATT network. It is unlock. It does support 850/1900mhz, but the spec said these frequencies are only for GSM and GPRS.

 

Vodafone K5150 (also K5150H) is a new 4G LTE Cat4 USB Stick from HUAWEI to support maximum download speed to 150Mbps and upload speed to 50Mbps. The HUAWEI K5150 supports LTE band 1, band 3, band 7 and band 20(800/1800/2100/2600MHz). Like its predecessor HUAWEI K5005, the unlocked K5150 Vodafone internet stick could also support 3G UMTS/DC-HSPA+ & 2G GRPS/GSM network.

Specifications:
* 4G LTE FDD Band 1/3/7/20: 800/1800/2100/2600MHz
* 3G DC-HSPA+/UMTS/WCDMA 900/2100MHz
* GSM/GPRS 850/900/1800/1900MHz

 

Thanks,

Justin


Justin,

 

this modem will only work on AT&T in 2G (GPRS/EDGE) model. It does not have the necessary AT&T bands on either 3G or 4G radio. In order to fully function on A&T LTE network, your modem needs to support the following frequencies:

 

2G: 850/1900MHz

3G: 850/1900MHz

4G: Bands 2,4,5,17 (1900,1700,850,700MHZ)

 

ACE - Professor

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1.7K Messages

9 years ago

Justin,
 This Asian,Australia and EU phone can only work in 2G & maybe in some area of USA with AT&T coverage.
3G and 4G will not work!!! DO NOT waste your money!!!!!
 

Contributor

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1 Message

9 years ago

So i have a phone that i got from a friend that i believe he may have gotten from china.  It is a lenovo and says the bandwiths are 850/900/1800/1900 mhz and 850/2100 mhz.  Will this work with AT&Ts 4G service as well as 3G.  Im planning to switch to them.

ACE - Professor

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1.7K Messages

9 years ago

As my post before,most cell phones you can buy in Mainland China are mostly for their local market.
This Lenovo famous Brand name phone will work on 2G GSM all over the world .
That's why in Mainland China they called it "WORLD/INTERNATION PHONE " 🙂
3G you may get limited coverage or none.

4G?? No way.

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