iphone 4 weak signal

[slople]

Hello, I have just bought an iPhone from USA and it has a very weak signal reception, two bars in a good coverage. It is one of the first models produced. The phone is from at&t, but I have the gevey sim adapter to unlock it. Someone told me that some models were made to work better in the USA and this should be the reason for this signal issue. That it works properly only with an at&t sim card. Has anyone a similar problem? I don´t know if it is a software issue or do I have to change the antenna,...
Thank you very much for your help,...

 

[iCrank]

Hello, I have just bought an iPhone from USA and it has a very weak signal reception, two bars in a good coverage. It is one of the first models produced. The phone is from at&t, but I have the gevey sim adapter to unlock it. Someone told me that some models were made to work better in the USA and this should be the reason for this signal issue. That it works properly only with an at&t sim card. Has anyone a similar problem? I don´t know if it is a software issue or do I have to change the antenna,...
Thank you very much for your help,...

Your country probably doesn't have sufficient coverage.

 

[iGaz]

I would say it is the gevey sim...

 

[slople]

Thanks for reply. Here is a very good network coverage, also this is my second iPhone4,... The first one worked perfectly, but unfortunately i broke it.
I have also tried with an other gevey adapter, but it got the same weak signal,...