Skip to comments.iPhone 4 Loses Reception When You Hold It By The Antenna Band?
Posted on 06/24/2010 1:10:28 AM PDT by PugetSoundSoldier
This is a reader video found on Macrumors forums illustrating something weird. When the guy holds the iPhone in his hands, touching the outside antenna band in two places, he drops reception. Placing the phone down gets him 4 bars.
We're not sure if he's doing something particularly weird, like holding the metal antenna in such a way that it's shorting out. But it is strange. Or, it could be just a bug in the software, showing no bars and no reception even when you do have reception. But, he does hold the phone with the glass, and it doesn't have this reception issue.
(Excerpt) Read more at gizmodo.com ...
Dials: left is phone on table, 804 kbps down/709 kbps up/449 ms ping
Center is phone held, 263 down/0 up/17769 ping
Left is in leather case, 594 down/42 up/448 ping
Seems someone forgot to test antenna gain when held. It can be fixed with a redesign of the PCB, the case, and the antenna layout, but that will require a new round of FCC (and all the overseas equivalent) tests, so expect a minimum of 3 months to redesign to fix this problem.
some serious flaws in iphone 4 so far
- poor reception when iphone is held by hand
- yellow spots on screen
- glass breaks easily when you drop it
This might be “Apple’s Vista”... Couldn’t come at a worse time, with Android phones outselling iPhones. Having the new iPhone 4 with several serious hardware errors could permanently cede the market lead to Android.
Also, I think it’s indicative of function following form. There’s a reason you don’t want metal over your antenna, especially when you can “short it” and create a full Faraday cage by holding it up to your ear (hand effectively sealing the back, because it’s grounded to the case). Plastic backs and sides may be ugly (like on the Android and WinMo offerings) but they work.
looks like the “great” feature of having the antenna as the body turned out to be a major design flaw
I’m just curious how this would pass usability testing... Seriously perplexed!
He’s just not holding his mouth right and PLEASE remove all outer tinfoil before using!
Apparently, there are several antennas built into the band separated by small gaps.
It may be possible to bridge the gaps with a wet finger creating inefficient antennas. The interesting number in the center is the 17 second ping time. I’d like to see some repeated experiments to see if there the results are consistent and what affects the antennas.
OTOH, the bars on the power graph tend to be useless. I spent the evening with five bars indicated on my iPhone 3G and no 3G connectivity. AT+T is annoyingly bad.
Another thing to remember is that this comes from Gizmodo, which is to tech journalism what the UK Sun is to newspapers. Gizmodo is the sleazy organization that paid $5k for a stolen iPhone prototype.
Yes, the MONSTER ping time grabbed my attention (along with the zero upload); it would be a symptom of really poor reception. The phone would be constantly dropping connection, and then trying to reacquire, and that would delay your ping.
The zero upload also points to this, as it has to restart the file each time the connection is reset, and that is why it never measured the upload speed. Downloads tend to packetize on the server better than uploads on the phone (memory and resources available for your TCP stacks).
That also seriously eats into the battery life as you need more power to connect to a cell than to maintain the connection. I think we see that in the screens, where you lost 8% of battery life in an hour; that’s a LOT of lost power in a relatively short time, when just trying to download a file.
As far as Gizmodo, they’re pretty accurate; buying a pre-release iPhone 4 is something most tech sources would have done, as it wasn’t stolen but actually lost, and when the finder attempted to return it to Apple, he was blown off by Apple.
And remember, we used to think the Enquirer was trash, but they’ve been the only one accurate about a number of “randy politicians”! Don’t throw out the story (especially when it has multiple Youtube videos from multiple people showing the exact same error) just because you don’t like what the outlet did once in the past...
LOL! That’s definitely thinking different...;)
When you touch an antenna conductor, it “de-tunes” the radiating element, usually lower in resonant frequency. The effect becomes more pronounced the higher in frequency you go.
You’re not really “shorting” anything out in the sense that something is going to blow a fuse - you’re effectively hanging a big, lossy lump of wet noodle off the end of the radiating element.
I’m rather surprised not only that this wasn’t found in testing, but that it made it through design. Most all of my RF work and studies were at HF to VHF frequencies, and having the user’s sweaty palm or fingers in contact with the radiating element would have been a no-no even at 150MHz - never mind up around 1.9 Ghz.
One thing that would be interesting is to see the difference between 850/1900 Mhz regions and 1900-only regions with this test.
Yeah, I was thinking you’re essentially taking a diversity antenna set and shorting the middle of the two antennas together through your hand - that will play all kinds of havoc with the impedance! Icky!
Just a few mils of polycarbonate over the antennas would solve the problem, but then the pretty outside is ruined. Form should follow function, not the other way around.
There are a number of plastic or leather cases available. Would that solve the problem?
Thanks for the ping. Sounds like similar problems other products have when they are rushed to market.
STOP TOUCHING THE ANTENNA!!
According to everything that I’ve heard, you don’t buy an iPhone for the phone service. In any case, I’m getting mine today. If I have problems with it, it’s going right back.
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