iPhones, iPods, & iPads forum

General discussion

Signal Fluctuation - Fundamental Design Flaw 3GS

by fjafri / August 22, 2009 3:49 AM PDT

I don't if this applies to the 3G model as well but I have discovered what appears to be a very fundamental design flaw. Ever since I bought the 3GS I noticed that the signal strength fluctuated, frequently fluctuating between a full 5 bars and a 1 bar or nothing. I tried to find the answer to this problem on various forums with some weird explanations like attaching a USB cable or a scotch tape to the sim. Nothing I tried improved this. I noticed that it seems to drop just when you made a call and recovered immediately after the call.

This made me wonder if it had anything to do with how the phone was being held. Some users were saying that two identical units would report different signal strengths at the same location in the same network.

Anyway after a lot of experimenting I discovered that the iPhone 3GS appears to be extremely sensitive to being held on the lower 1/3rd part of the handset. Holding the phone in the top half recovers a full signal within a few seconds (15/20 secs)!!!!

You can try this yourself. Putting the phone down on the table or picking it ensuring the bottom half remains uncovered seems to work. Covering the bottom half starts to drop the signal.

The design flaw is that the receiving antenna should be placed at the top of the phone which is least likely to be covered when held. Either way it's a flaw that Apple should recognize and fix. Other handhelds don't seem to suffer from this characteristic.

Discussion is locked
You are posting a reply to: Signal Fluctuation - Fundamental Design Flaw 3GS
The posting of advertisements, profanity, or personal attacks is prohibited. Please refer to our CNET Forums policies for details. All submitted content is subject to our Terms of Use.
Track this discussion and email me when there are updates

If you're asking for technical help, please be sure to include all your system info, including operating system, model number, and any other specifics related to the problem. Also please exercise your best judgment when posting in the forums--revealing personal information such as your e-mail address, telephone number, and address is not recommended.

You are reporting the following post: Signal Fluctuation - Fundamental Design Flaw 3GS
This post has been flagged and will be reviewed by our staff. Thank you for helping us maintain CNET's great community.
Sorry, there was a problem flagging this post. Please try again now or at a later time.
If you believe this post is offensive or violates the CNET Forums' Usage policies, you can report it below (this will not automatically remove the post). Once reported, our moderators will be notified and the post will be reviewed.
Collapse -
You remind me of a situation I went through a long time ago.
by tleMega / August 22, 2009 4:20 AM PDT

I used to have severe WiFi signal and connection problems two years ago. My MacBook would run slow, and throw errors at me in Network Utility all the time. At one point, I wondered what stationary objects in my home could have been causing any interference that could have been contributing to my problems. I scoured the place for whatever may have been problematic; I tried moving some AV receivers and transmitters around (for my TVs), moving the router to different rooms, among other things. At one point, I had given up a lot hope to find a solution to my wireless troubles. I then noticed my old Pentium III HP Desktop sitting in the room. I had installed a wireless card into it three years ago, but since I got my MacBook Pro, it became obsolete. I had it unplugged too. Nevertheless, I tried removing the antenna to the wireless card, and I think I even tried removing it from the computer. Around the same time, my MacBook experienced a slight increase in network performance and a small decline of errors. I thought I had found the problem! But of course, removing an antenna to a wireless card in an old machine that has no power sounds extremely stupid, does it not? Of course, the next day, my problems returned to haunt me.

My point is, you are making this claim that seems unrealistic. If your iPhone has signal fluctuations, it is most likely because (a) AT&T has extremely unreliable service in your area or (b) your area is coated in wireless traffic and interference. You'd be surprised how much computing electronics can affect iPhones. My 3G can hardly receive decent service if all of my equipment is on and talking to the router in the same room; I can go the other side of the house and have normal signals, but I get no bars on 3G in my tech room.

I would assume the antenna in the iPhone would be near the top of the device, but I can't say for sure. That's just common sense. I can't help but say I think you are overreacting here. Unless the bars are dropping from 5 to 0 bars in under a second and continue to do so repeatedly (as if you were turning a volume dial up and down continuously), I would think your phone is working fine. Otherwise, take it to your nearest Apple Store and have them look at it. Holding the phone up higher will probably net it a better signal anywhere, but here, my iPhone gets the same, consistent signals that I'm used to no matter where I put it. I think you need to reevaluate what's going on with your phone.


Collapse -
It's True
by fjafri / August 23, 2009 7:12 AM PDT

Test it yourself if you're so pessimistic. I have literally tested this from every aspect. Holding the phone like a normal phone covers the bottom part and the signal drops adversely - and I do mean from 5 bars to 1 or none. Holding the phone at the top brings the bars right back again and again. Thereis only one explanation for this, the antenna is at the bottom!

The flaw in the design isn't that the antenna is atthe bottom, it is that when thisarea is covered the signal can drop so dramatically. I have a 3 GS and I can't say if this happens with other models...

Collapse -
I have the original 3G
by tleMega / August 23, 2009 1:43 PM PDT
In reply to: It's True

and I am not seeing any of the effects that you're describing when I change how I hold it. Leaving it on a table or carrying it around doesn't automatically change network conditions either. Take your phone into Apple if simply moving it around as you have described is truly changing your phone's performance.

My phone is protected and powered by an Incase Power Slider case. It's twice as thick, and little taller, and has twice as much operating capacity. I can squeeze two days of use out of it, WiFi on or off regardless. If the antenna was at the bottom of this model, would not the case be obstructing it? The battery plugs into the 30-pin connector on the bottom, and extends the chin of the phone to allow for a speaker grill and a Mini-USB port for charging and syncing. I think the case extends the chin somewhere from 1/4 to 1/3 of an inch outward. I get full signals in most places anyhow. Clearly this does not seem to be related to original 3G. The 3GS has a far more powerful HSPA radio, so I have trouble believing that it would be much more sensitive to 3G signals. Once again, I would think that either your phone is defective or your coverage is lackluster at your location. While I can't say for sure where the internal antenna is, if you're a brave soul, you could attempt cracking it open, but I would not recommend doing so. Take it to Apple and see what they say. Good luck.


Collapse -
Could Be The Other Way
by Zuschlauer / September 3, 2009 1:47 AM PDT
In reply to: It's True

Could be that the antenna is at the top. The electrical nature of your hand/body may be improving reception. Touching an antenna often improves reception. In the days of rabbit ears you sometimes had to hold the antenna to watch the show.

I have the same issue with my first generation iPhone. Signal strength goes down during a call and back up when the call ends. Another iPhone owner reported the same problem on the Apple iPhone forums. It becomes very difficult sometimes to hear the caller. I don't remember having this problem with my RAZR, but the audio quality was generally always lower with that phone.

As the other guy said, if you have other cell or portable phones, wifi devices, you may have a difficult time isolating interference. Cell phones cannot be talking with the tower continuously or they would go dead in a few hours. They only test the signal strength for some fraction of a second in all probability. When you call someone you get the real, continuous, signal strength. Signal strength is not as important as the signal to noise ratio, so all those other devices can cause intermittent problems as they may undergo a burst of activity and interfere with your signal. My wifi modem is used by several computers in my household and my be pretty busy at any time.

Since antennas always receive, even unpowered units are part of the environment. But it is hard to see that they would generate enough signal strength on the card to matter. It is more likely that neighbors with signal strength boosting routers are a problem. Any wifi router that will cover a whole house with signal will interfere with the neighbors signals. That could be you. I get a strong signal from my neighbor across the street's router. It is stronger than my next door neighbor's. These routers are out of spec, but sold anyway. They violate regulations, but try to get an FCC inspector to come out to your house, good luck.

Defective electronics in your house could be broadcasting static on cell phone frequencies or all frequencies, also. I've had so many phone problems that I have checked out various forums and there are too many unmonitored electronic systems in our lives today to easily track down interference.

Popular Forums
Computer Newbies 10,686 discussions
Computer Help 54,365 discussions
Laptops 21,181 discussions
Networking & Wireless 16,313 discussions
Phones 17,137 discussions
Security 31,287 discussions
TVs & Home Theaters 22,101 discussions
Windows 7 8,164 discussions
Windows 10 2,657 discussions


Help, my PC with Windows 10 won't shut down properly

Since upgrading to Windows 10 my computer won't shut down properly. I use the menu button shutdown and the screen goes blank, but the system does not fully shut down. The only way to get it to shut down is to hold the physical power button down till it shuts down. Any suggestions?