[FF22]

Just read another article on the new Iphone (supposedly older ones used a miscalibration to show higher than actual values) and there was this quote:

"But the company said that any phone will show reduced reception if held in a way that covers the antenna, usually mounted at the rear and bottom of a phone."

So, in my new 9650 (Bold) where are the various antenna? Bluetooth, Wifi and RADIO (most important)?

Where/how should we hold our phones to avoid interfering with signals?

[Pi Guy 3.14]

I believe the antenna is at the bottom on the 9700, not sure about the 9650 but I have tried several, several times to lose signal from holding it differently and I cannot. And yes, my indicator is set to -dB and not bars.

And if it does fluctuate, it will fluctuate back up indicating the it does not matter where you hold it.

[Xopher]

If I remember correctly, the main issue with the i4 is that the antennas are actually the metal edging on the outside of the device. If your hand touches multiple edges, it crosses the antennas and causes problems (sort of shorts out the signals). Supposedly, putting it in a case keeps your hands from shorting out the antennas.

With that in mind, I would think that since the BlackBerry antennas are on the inside, there wouldn't be as much of a chance for blocking out the signal too much.

[pcgizmo#IM]

Apple is using this to demonstrate the proper holding technique

[MrObvious]

Haha plk. I'm not sure where on the 9630/50, but it's probably the same as the 9700. And yes the problem with the iPhone 4 is that the antennas (it's two pieces on one piece of steel) are transmitted right in the lower left corner and the human body has water and it affects signal so much that it dies. There is a nice article on Steve Gibson's (Security Now! podcast owner) blog about it.

[Pete6]

The antenna is at the bottom of the phone on every BlackBerry I have dismantled.

The antenna placement is not the problem however. The problem is the metal skin and electrically conductive touch screen on the iPhone.

[theonecid]

So does that mean that the iPhone 4 is a lost cause or can it eventually get fixed with newer OS' do you think ?

[Pete6]

I honestly do not know. I have not seen an iPhone 4 and I know nothing of the exact construction. This would be essential in determining the problem and a fix.

Steve (can no one else speak for Apple?0 says that it is a software fix and that it would be out by last Monday. I have yet to see that on Engadget although I might have missed it.

Radio frequencies at around 1Ghz propagate tyhrough conductive materials like quicksilver and try hard to go where the electronic designer does not want them to go. I suspect that this is the root of the problem with the iPhone 4. The electronics are working perfectly but the case is causing a percentage (don't know how much) of the RF energy to not be routed to the antenna. It seems to be getting into the case.

The antenna is tuned to a particular frequency. It resonates just like a school ruler vibrated against a table.

The antenna is also built to be as near as possible to be omni-directional so that it can talk to any cell tower anywhere around it.

A cell phone puts out approximately 5 Watts of RF power so any leakage is not good.

It would seem that the RF is circulating on the outer skin of the phone and not getting out to the wide, wide world and therefore the antenna and its electronics is working hard but getting confused because its careful tuning is looking a bit like a wet sponge.

However there is worse. Enter a human who picks up the iPhone. The RF that is all over the case (harmless by the way) is now furter attenuated by being conducted into the human.

This is a bit like being smotherd by a pillow. You shout out but can't be heard.

I think that Stevie has a bigger problem on his hands than he is currently admitting.

I stress that without actually examining this problem on a bench, with instruments I cannot offer more than a guess but I have been around RF and electronics for a very long time and this looks quite like what I postulate.

Branta may also have insights here as he too works with electronics and radios.

[jlb21]

Basically, IMHO, stupid deign flaw that they should have caught before releasing the device. And they probably did and kept it a secret.

[theonecid]

I honestly do not know. I have not seen an iPhone 4 and I know nothing of the exact construction. This would be essential in determining the problem and a fix.

Steve (can no one else speak for Apple?0 says that it is a software fix and that it would be out by last Monday. I have yet to see that on Engadget although I might have missed it.

Radio frequencies at around 1Ghz propagate tyhrough conductive materials like quicksilver and try hard to go where the electronic designer does not want them to go. I suspect that this is the root of the problem with the iPhone 4. The electronics are working perfectly but the case is causing a percentage (don't know how much) of the RF energy to not be routed to the antenna. It seems to be getting into the case.

The antenna is tuned to a particular frequency. It resonates just like a school ruler vibrated against a table.

The antenna is also built to be as near as possible to be omni-directional so that it can talk to any cell tower anywhere around it.

A cell phone puts out approximately 5 Watts of RF power so any leakage is not good.

It would seem that the RF is circulating on the outer skin of the phone and not getting out to the wide, wide world and therefore the antenna and its electronics is working hard but getting confused because its careful tuning is looking a bit like a wet sponge.

However there is worse. Enter a human who picks up the iPhone. The RF that is all over the case (harmless by the way) is now furter attenuated by being conducted into the human.

This is a bit like being smotherd by a pillow. You shout out but can't be heard.

I think that Stevie has a bigger problem on his hands than he is currently admitting.

I stress that without actually examining this problem on a bench, with instruments I cannot offer more than a guess but I have been around RF and electronics for a very long time and this looks quite like what I postulate.

Branta may also have insights here as he too works with electronics and radios.

Thanks for this complete information. I agree with everything you said.

Basically, IMHO, stupid deign flaw that they should have caught before releasing the device. And they probably did and kept it a secret.

You're right, I wonder how they let this big one through the testing phase. Wow.

[Pete6]

BGR posts Apple's fix Apple releases statement about iPhone reception, fix due in “a few weeks” � Boy Genius Report

and, here is a rather adult translation Daring Fireball: Translation From Apple's Unique Dialect of PR-Speak to English of the 'Letter From Apple Regarding iPhone 4'

[RadioRaiders]

So does that mean that the iPhone 4 is a lost cause or can it eventually get fixed with newer OS' do you think ?

The iPhone4 antenna problem is a hardware problem. It's the first cellphone that has the raw metal antenna elements on the outside of the phone. When you touch the element, it changes the antenna properties, and practically kills the functionality of it. If you touch one antenna, the other still works, but if you touch both at the same time, you kill both, and have a massive signal loss.

The "patch" Apple is issuing is "smoke and mirrors" to make people look away from the hardware problem, and give them the feeling that Apple is doing something. In reality I think Apple will try everything possible to avoid recalling 1.7 million phones.

[google123]

Maybe they didn't realize this would b a problem since the test mules had covers on them that cover the metal band much like the bumpers. Remember the phone that Gizmodo ended up with had a plastic case on it that just happened to shield the users hand from the metal band. People with the bumpers on the phones don't seem to have much trouble with signal loss like those not using anything on the metal band. If that's the case, apple should provide free bumper with purchase until the problem is fixed.

Posted from my CrackBerry at wapforums.crackberry.com

[Pete6]

The iPhone4 antenna problem is a hardware problem. It's the first cellphone that has the raw metal antenna elements on the outside of the phone. When you touch the element, it changes the antenna properties, and practically kills the functionality of it. If you touch one antenna, the other still works, but if you touch both at the same time, you kill both, and have a massive signal loss.

The "patch" Apple is issuing is "smoke and mirrors" to make people look away from the hardware problem, and give them the feeling that Apple is doing something. In reality I think Apple will try everything possible to avoid recalling 1.7 million phones.

I completely agree. The metal case, conductive screen will change the impedance (reflection and return loss) of the antenna once the case is fitted and again whenever anyone touches the case or the screen.

RF is notorius for finding its way all over the place. Apple have a major problem on their hands with this one and serve them right, imo.

The only real fix is a total recall (Hi Arnie) of all phones and then to fit a new case.

Apple will try 3 things
1). a software fix, as you say, smoke and mirrors. it ainlt gonna work.
2). offer a free plastic case to all users. thsi will sowrk somewhat
3). total recall and fit new cases to all iPhone 4s.

Apple should concentrate more on function and less on form.

[Pi Guy 3.14]

Why give away free bumpers when you can charge 30 bucks for it....?

Posted from my CrackBerry at wapforums.crackberry.com

[RadioRaiders]

Oh, to get back to the original question of "where are the antennas", generally speaking, most phones put them towards the bottom of the phone these days, because the top part of the phone is usually pressed against your head during a call.

Normally, the average "body loss" is about 3-6dB's (signal attenuated by the human body). If you put your hand directly over the antenna, it shouldn't be much more than 3-6dB's, but could be up to 10dB or so depending on various things (is the antenna poorly shielded? Are you in a fringe reception area? etc) I tried on several phones (RIM, Nokia, Motorola), holding them, putting them under my arm, and couldn't get the signal to drop more than 4dB's on average, once or twice 10dB. If you see a 20dB drop from simply holding your phone (like iPhone4 people are reporting to see regularly from just holding it), something sounds wrong. That's too much.

To see the RSSI in dBm on your BB press ALT and the letters NMLL. Or download my app OTA in your BB browser at cellumap.com/ota

Oh, and the 8900 seems to have the antenna on the bottom:

[Pete6]

I agree entirely RadioRaiders 3 - 6 dB is about right.

For those not familiar with decibels, the decebel scal is logarithmic. This would mean that a drop of 3.5dB would be half power whilst a drop of 6dB would be half the voltage.

If you base normal reception at about -100dB (a bit low but it's a nice round number) then 3 -6 dB down is not a huge amount until you consider noise, reflection and/or multipathing (bouncing off buildings), the weather. then this becomes quite a serious loss. Multi-pathing is a real problem for cell phones. In this, some of the signal goes one way whilst other parts get bounced off reflective surfaces like buildings. GSM has an algorithm that is designed to kill multi-path signals and only takes the strongest from any one source. This is good until you realize that the mult--pathed signal is now lost completely. Thsi can be up to 49% of the phone's output say, 3dB. Add another 3 -6 dB for the antenna loss and your are in trouble.

Now wait till you have wet hands.

[khager]

Apple is using this to demonstrate the proper holding technique

aaaaaaaaaaaahahahahahahahhaha

[FF22]

RadioRaiders:

Thanks for getting back to the original question. (I was just going to ask for that since the topic did swing solely to the iphone).

And while we are here: we want those negative numbers to be more or less negative for a good signal and what is the value when degraded. I guess the MINUS throws me off (even with my science - biology - background)

[RadioRaiders]

RadioRaiders:

Thanks for getting back to the original question. (I was just going to ask for that since the topic did swing solely to the iphone).

And while we are here: we want those negative numbers to be more or less negative for a good signal and what is the value when degraded. I guess the MINUS throws me off (even with my science - biology - background)

Oh, the "lower" the number the worse. Between -100 to -110 or so is very bad, you drop at about -110. From -90 to -100 is borderline, it's fine to hold a call, but if you walk behind a wall, you could drop 10dB's or more and be in the sub -100 range. -80 to -70 is good. Over -70 is really strong. -40 is probably the best you can get.

PS- I just started a thread where everyone can test for themselves and post their results, so it would be interesting to see what people are experiencing on average:
http://forums.crackberry.com/f2/what...1/#post5310408

.

[MrObvious]

Actually even if the iPhone4 loses reception with the antenna, it still gets better reception than the 3Gs. Most people put their iPhones in condoms anyway (I do with my Tour) so it shouldn't be a problem.

[FF22]

Actually even if the iPhone4 loses reception with the antenna, it still gets better reception than the 3Gs. Most people put their iPhones in condoms anyway (I do with my Tour) so it shouldn't be a problem.

The "condom" should not affect the Tour since the antenna is not external so you are not directly touching it. Now I don't know if you contact the metal on the usb port.

But, off topic, my Creative Zen M had an FM radio and the headphone wire was it antenna.

[ItnStln]

Great read.

Posted from my CrackBerry at wapforums.crackberry.com

[Snarfler]

with my 9530, I lose 15 dB going from holding with thumb at bottom and index finger at top in portrait, to holding it in my palm up against my head.

[joeldf]

On my Pearl 8100, the antenna is at the bottom too, beneath the bottom cover piece.

If I cup my hands around the bottom totally, the signal strength will drop, but it works it's way back up after a few seconds.