More on the iPhone 4 signal issue
Previously, I did some simple testing of reception strength on my iPhone 4 and concluded that I couldn’t see any problems. I’ve now done some more thorough testing, however, and have reason to think I was wrong. Warning: this is very long and nerdy.
UPDATE: read Anandtech’s article, they figured out how to make the iPhone 4 display true signal-to-noise ratios and have thus been able to use more rigorous science than I could. They agree with my conclusions though!
A very interesting read for those interested in the iPhone 4 antenna issues.
Source: penllawen

