G1 Testing – Part 3
on Apr.05, 2009, under Networking, Technology
Part my “phone decision tree” is carrier selection. The G1 and the iPhone are both GSM phones that can be unlocked from their respective networks. I’m somewhat familiar with AT&T’s network – I used to have their service and found it good, and Doug currently has their service, and we’ve compared Verizon/AT&T coverage on occasion with comparable results. To evaluate T-mobile, I purchased a pre-paid SIM for their network.
At home, I get about 2 bars out of 4 on the G1 with T-mobile pre-paid. This is comparable to my Verizon EV-3-bars and 1x-2-bars, and Doug’s about 2 bars of AT&T. At my parent’s place I get full signal, same as Verizon. At work, I expect full strength being a stone’s throw from their tower.
For further comparisons, I did about a 100-mile road test and managed to get Chris B. to go along and observe signal strengths. Here were the generalized results:
- Home to Roxbury: T-mobile > Verizon
- Roxbury to Fannettsburg (along turnpike): T-mobile = Verizon
- Fannettsburg to Ft. Loudon (route 75): Both poor, T-mobile < Verizon
- Ft. Loudon to Chambersburg (route 30): Marginal Verizon, but mostly no T-mobile
- Chambersburg to Caledonia (route 30): Both very good, T-mobile = Verizon
- Caledonia to Shippensburg (route 233, Ship Rd): Both generally poor, T-mobile = Verizon
- Shippensburg to Home: Both good, T-mobile = Verizon
These observations were generally consistent with the published T-mobile and Verizon coverage maps.
With these observations, T-mobile appears to be a viable carrier for the locations I spend most of my time. But cell service is nice to have places where you don’t spend a lot of time as well. Looking at the state-wide zoom level for AT&T, Verizon, and T-mobile, it appears clear the T-mobile is really, really lacking. AT&T and Verizon appear to be about comparable.
In performing this comparison, I found it hard to believe that there were no good tools to show multiple providers coverage areas simultaneously. Verizon’s coverage map was good, with a google-maps-like drag-scroll interface. AT&T and T-mobile were not. In all cases the zoom levels for the maps poorly corresponded, making comparisons that much more difficult.
What about roaming? I had read/heard about T-mobile and AT&T having mutual roaming agreements. Can I purchase T-mobile service and use AT&T’s network? I tried selecting AT&T as the provider with my T-mobile pre-paid SIM, and it did not work. That does not necessarily mean that it would not work with a “real” T-mobile plan. However, I would really expect the provider coverage maps to show areas that they mean to cover with roaming, and T-mobile does not show anywhere near AT&T’s footprint. Besides, I have read of peering agreements changing over time without notice, so even if it worked now, it might not forever. I’ve decided it’s not worth getting a real T-mobile account just for testing internetwork roaming.
As a break from the analysis, I did manage to get to try T-mobile’s EDGE data service on the G1. I’m not sure exactly how it happened. I upgraded to R33 last night, and while around my parents house, a new “G” icon appeared with in/out data arrows. An app that tracks data usage confirmed that it was the 2G radio interface, and that it was passing traffic. I was able to play around with Google maps, web browsing, IM’ing, ping, and ssh using EDGE today, and the performance was fine. This evening however, it stopped working and the browser shows a page saying that the G1 needs a real data plan. Still, I was pleased to have the brief opportunity.
What about 3G? If I use the G1 on AT&T can I use 3G? The answer appears to be no, due to different frequencies/bands used for T-mobile’s and AT&T’s network and handsets. But T-mobile does not have 3G anywhere near me anyway. AT&T does, so if 3G is a requirement, the iPhone has to be the way to go. Otherwise, using the G1 on AT&T locally should be no different 3G-wise than using it on T-mobile.
Conclusion: T-mobile isn’t a viable carrier for me. The G1 can work on AT&T’s network as long as I don’t need 3G. If I need 3G, the iPhone, AT&T (and going to Carlisle or Hagerstown, for now, at least) is the only option. Do I need 3G? Probably not.
