iMore

I am using a iphone 3g and when I go to my place on the river I loose signal to my phone. My friends up there use sprint and t-mobile, they get service just fine. I use ATT which may be my problem. I rember back in the day our phones would jump to and use any tower you were close to. Are those days gone now? Is there a way to force my Iphone to use those other towers? I tried to switch the 3g off then did a reboot,didnt help. I also turned the data roaming on and that didnt help either. Will JB help with that at all?