I worked in National Reporting to the Presidents and Vice Presidents of Verizon Wireless so here is how this works. Airwaves (Frequency Blocks) are auctioned off in certain areas through an FCC auction. When I am traveling with my Verizon phone I use the Verizon network at a certain frequency (right now LTE will soon operate in the 700 Megahertz frequency when LTE is available) But, if I have a different company roaming on the Verizon Network I am offered a lower frequency plus my calls are given second priority over their carriers calls.
Recently I had switched to try Cellular South here in Mississippi only to travel outside of Mississippi and not be able to use their data network, not in TN, Not in KY, Not in VA, Not in WV, Not in PA, Not in Ohio, Not in SC, Not in NC. So far that is where I have tried I get a cell signal but no data allowed on roaming only in some areas.
Therefore, get a contact so you can make a call. Here in my house in MS Cellular South has their own tower up the road but a weak signal. I switched back to Verizon and I have 3 and 4 bars on my Droid (Which I soaked in water recently and still works). (Baked in oven on 90 degrees for 44 hours without battery and let sit on counter without battery for two days and it works like a gem).
Hope my rambling helps...lol
