A new article in the research group's Electronics Blog notes that the "signal woes" of iPhone 4 are not a unique problem, and "may not be serious."
"Underplayed in the discussion is the fact that all phones are subject to interference from the human who is using them," writes Mike Gikas. "And even if the alleged signal loss is real, there's an absence of hard evidence that iPhone 4 reception is problematic compared to past iPhones; indeed, there's evidence of just the opposite."
The group adds, "most of the web sites reporting dropped signals and even dropped calls have demonstrated several techniques, or 'death grips' for recreating the problem (which we've yet been able to reproduce in a meaningful way). But those almost always require squeezing the phone hard, in an unnatural way. Those grips may also produce sweaty palms from exertion, with the sweat increasing conductivityand possibly the degree of signal loss."
(Update: Gikas has subsequently reported that "while we've been unable to date to create the reported conditions in our National Testing Center in Yonkers, New York," he has been able to "reproduce the signal loss that's at the heart of the controversy," in informal testing, noting "there's some question about whether the drop in displayed signal is merely a metering issue, and whether call quality or the ability to place calls is affected." The update also points out that there are many readers who "report fine and consistent signal experiences with their new iPhones")
Gikas cited lab testing performed by Anandtech, which "determined that the iPhone 4 performs much better than the 3GS in situations where signal is very low, at -113 dBm (1 bar)."
That report further noted, "previously, dropping this low all but guaranteed that calls would drop, fail to be placed, and data would no longer be transacted at all. I can honestly say that I've never held onto so many calls and data simultaneously on 1 bar at -113 dBm as I have with the iPhone 4, so it's readily apparent that the new baseband hardware is much more sensitive compared to what was in the 3GS."
Using a cover, iPhone 4 performed even better. "With my bumper case on, I made it further into dead zones than ever before, and into marginal areas that would always drop calls without any problems at all," Anandtech wrote.
"It's amazing really to experience the difference in sensitivity the iPhone 4 brings compared to the 3GS, and issues from holding the phone aside, reception is absolutely definitely improved. I felt like I was going places no iPhone had ever gone before. There's no doubt in my mind this iPhone gets the best cellular reception yet, even though measured signal is lower than the 3GS."
Consumer Reports concluded that even if problems do materialize, "Apple's Steve Jobs helpfully reminds new iPhone buyers that 'you can return your undamaged iPhone to any Apple Retail Store or the online Apple Store within 30 days of purchase for a full refund.'"