Design Flaw in iPhone 4, Testers Say
 

http://www.nytimes.com/2010/07/13/te...apple.html?hpw

"Consumer Reports, America’s trusted source of product reviews, said
it would not recommend the iPhone 4 because of a hardware flaw with
its antenna that sometimes resulted in dropped calls.

"... its antenna, which is built into a steel band that encases the
phone.

"After users reported problems with signal strength and dropped calls
when they touched the lower-left portion of the phone, however, Apple
suggested that consumers hold the phone differently or use one of many
bumpers to insulate the antenna. It also said that all phones suffered
from similar problems when they were cradled a certain way.

"These comments were widely laughed at in gadget blogs. "

Just thought I would submit this to the Laughing Academy.

73's
Richard Clark, KB7QHC

Design Flaw in iPhone 4, Testers Say
 

On 7/12/2010 8:30 PM, Richard Clark wrote:

http://www.nytimes.com/2010/07/13/te...apple.html?hpw

"Consumer Reports, America’s trusted source of product reviews, said
it would not recommend the iPhone 4 because of a hardware flaw with
its antenna that sometimes resulted in dropped calls.

"... its antenna, which is built into a steel band that encases the
phone.

"After users reported problems with signal strength and dropped calls
when they touched the lower-left portion of the phone, however, Apple
suggested that consumers hold the phone differently or use one of many
bumpers to insulate the antenna. It also said that all phones suffered
from similar problems when they were cradled a certain way.

"These comments were widely laughed at in gadget blogs."

Just thought I would submit this to the Laughing Academy.

73's
Richard Clark, KB7QHC

I can't tell from your comments if you think there is a problem with the
phone or Consumer Reports.

From what I've heard there are repeatable problems, but I've heard no
coherent explanation of what might be occurring.

The thing that seems to be consistent is that left handed users have
more reported problems than right handed users.

tom
K0TAR

Design Flaw in iPhone 4, Testers Say
 

On Mon, 12 Jul 2010 21:19:06 -0500, tom wrote:

On 7/12/2010 8:30 PM, Richard Clark wrote:

http://www.nytimes.com/2010/07/13/te...apple.html?hpw

"Consumer Reports, America’s trusted source of product reviews, said
it would not recommend the iPhone 4 because of a hardware flaw with
its antenna that sometimes resulted in dropped calls.

"... its antenna, which is built into a steel band that encases the
phone.

"After users reported problems with signal strength and dropped calls
when they touched the lower-left portion of the phone, however, Apple
suggested that consumers hold the phone differently or use one of many
bumpers to insulate the antenna. It also said that all phones suffered
from similar problems when they were cradled a certain way.

"These comments were widely laughed at in gadget blogs."

Just thought I would submit this to the Laughing Academy.

73's
Richard Clark, KB7QHC

I can't tell from your comments if you think there is a problem with the
phone or Consumer Reports.

Hi Tom,

By any account, there's a problem. Now, as the iPhone has had
demonstrable connection issues in the past, it was blamed on AT&T who
bore the brunt of that criticism.

Reports long following this past connection problem has borne out that
AT&T had adequate 3G capacity, and AT&T chose to take the bullet for
their customer (Apple, if anyone has lost track) who had a marginal
design in their protocol stack (poor through-put and high retry
traffic).

From what I've heard there are repeatable problems, but I've heard no
coherent explanation of what might be occurring.

The NYT article's symptomology bears out across many reports from a
variety of sources.

The thing that seems to be consistent is that left handed users have
more reported problems than right handed users.

That would be apocryphal, at best.

The short answer is that fashion trumps technology. The rising trend
of using the iPhone as an eReader flies in the face of what was
formerly a nebbish activity. Fashion forced the turnaround, not the
technology (I've been reading books on my Palm Pilot for 6 years - I
have not suddenly become an über-hip literary savant overnight by
virtue of that trend as anyone here will quickly testify.)

The only thing that remains a mystery, for me if for no one else here,
is the literal specification of the antenna. Google (gasp) fails me.

73's
Richard Clark, KB7QHC

Design Flaw in iPhone 4, Testers Say
 

On 7/12/2010 9:46 PM, Richard Clark wrote:

The only thing that remains a mystery, for me if for no one else here,
is the literal specification of the antenna. Google (gasp) fails me.

73's
Richard Clark, KB7QHC

And that does seem to be the crux of the matter. What is the antenna?
And what does it interact with that's not, be it part of the phone or
part of the user?

tom
K0TAR

Design Flaw in iPhone 4, Testers Say
 

On Mon, 12 Jul 2010 21:54:17 -0500, tom wrote:

On 7/12/2010 9:46 PM, Richard Clark wrote:

The only thing that remains a mystery, for me if for no one else here,
is the literal specification of the antenna. Google (gasp) fails me.

73's
Richard Clark, KB7QHC

And that does seem to be the crux of the matter. What is the antenna?
And what does it interact with that's not, be it part of the phone or
part of the user?

Hi Tom,

The antenna is reported as being the metal trim that surrounds the
perimeter of the phone. As that is much too large for the frequencies
involved to be taken literally, there is more to the story that
remains clouded. Maybe I'm wrong....

If the loop (or dipole) is suitably matched, it doesn't give much
polarization diversity. Perhaps no phone does anyway.

Insofar as being "part of the user," we well know the EM of HTs and
the hand/body contribution. If such were the case, then this would be
an agnostic problem that users of all mobile phones would complain of
(which mildly refutes what the gadget blogs dismissed). On the other
hand, the über-hip, whose complaints are more vocal for their "pain,"
would be outraged at the notion of their simply enjoying the identical
experience of techno-trash. Amazing what a 10 fold cost differential
brings to your perception of quality of service.

73's
Richard Clark, KB7QHC

Design Flaw in iPhone 4, Testers Say
 

In article ,
tom wrote:

From what I've heard there are repeatable problems, but I've heard no
coherent explanation of what might be occurring.

The thing that seems to be consistent is that left handed users have
more reported problems than right handed users.

A drawing of the iPhone 4 I saw recently (I think it was in a recent
SJ Mercury News) indicates that there is a deliberate gap in the metal
rim of the iPhone 4 - the rim that serves as the antenna. This gap is
located near the lower left corner of the phone.

If I understand correctly, the iPhone 4 has a tendency to drop calls
if it's held in a way which allows the user's hand to bridge across
this gap... presumably "short-circuiting" the antenna in some way.
A left-handed grip on the phone would put the user's palm right across
the gap - this may be the worst-case situation.

Applying an insulation of some sort to the area of this gap (an iPhone
case, or duct tape), or holding it in a way which doesn't cause the
hand to bridge the gap, reduces or eliminates the problem.

It sounds as if this iPhone has some sort of dipole or loop antenna
design, which requires that a high RF impedance be maintained at this
point. The low RF impedance of human skin is apparently enough to
de-tune or load the antenna in some way which disrupts its function.

Has anyone run across a web site showing a "tear-down" of the iPhone
4, which might clarify its antenna design?

--
Dave Platt AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

Design Flaw in iPhone 4, Testers Say
 

In article ,
tom wrote:

On 7/12/2010 9:46 PM, Richard Clark wrote:

The only thing that remains a mystery, for me if for no one else here,
is the literal specification of the antenna. Google (gasp) fails me.

73's
Richard Clark, KB7QHC

And that does seem to be the crux of the matter. What is the antenna?
And what does it interact with that's not, be it part of the phone or
part of the user?

tom
K0TAR

There are a number of issues here, that are Mutually Exclusive, but
added together cause the iPhone4 to seem to have some problems.

Issue One. Apple has already admitted that the Signal Level algorithm,
used in the IPhone4 was seriously flawed in how it displayed Signal
Level. (Bars) When the Phone displayed 4 or 5 Bars, it may actually only
be receiving at a 1-2 Bar Level. This they have corrected with a
Software Patch.

Issue Two. The Multi-Band Antenna design in the iPhone4 is a Kludge
Compromise at best, and burying it in the Metal Frame where Left Hand
users put the flesh against it, seriously detunes it. Apple is in the
process of hiring a small group of Engineers, with expertise in this
area.

The combination of these two issues seems to cause, what appears to be a
High Signal Level, to drop to "No Bars" when some users grasp the
iPhone4 in a particular way. The "Simple Fix" is don't hold it that way.
The more complex "Fix" is to redesign the Cellular Antenna, and move it
to the Top of the iPhone4. This would require that the BlueTooth/Wifi
antenna be redesigned as well. Apple is looking to do that in the 2nd
Generation iPhone4.

Just remember that Apple isn't particularly adept in the RF Arena, and
the iPhone/iTouch/iPad are their only small products that have RF
Antennas, this small. Also remember that some of their Laptops, of past
years, had some serious Wifi Antenna placement problems, and remember
that Wifi at that time was only a Single Band, not a Three Band System,
like the iPhone4.

Just saying.

--
Bruce in alaska
add path after fast to reply

Design Flaw in iPhone 4, Testers Say
 

Richard Clark Inscribed thus:

On Mon, 12 Jul 2010 21:54:17 -0500, tom wrote:

On 7/12/2010 9:46 PM, Richard Clark wrote:

The only thing that remains a mystery, for me if for no one else
here,
is the literal specification of the antenna. Google (gasp) fails
me.

73's
Richard Clark, KB7QHC

And that does seem to be the crux of the matter. What is the antenna?
And what does it interact with that's not, be it part of the phone or
part of the user?

Hi Tom,

The antenna is reported as being the metal trim that surrounds the
perimeter of the phone. As that is much too large for the frequencies
involved to be taken literally, there is more to the story that
remains clouded. Maybe I'm wrong....

I think you're right. "Design Flaw" Someone messed up testing big time.

If the loop (or dipole) is suitably matched, it doesn't give much
polarization diversity. Perhaps no phone does anyway.

Aren't cell stations vertically polarised. The one near me is, and one
of the IF's is smack on 144.005 Mhz.

Insofar as being "part of the user," we well know the EM of HTs and
the hand/body contribution. If such were the case, then this would be
an agnostic problem that users of all mobile phones would complain of
(which mildly refutes what the gadget blogs dismissed). On the other
hand, the über-hip, whose complaints are more vocal for their "pain,"
would be outraged at the notion of their simply enjoying the identical
experience of techno-trash. Amazing what a 10 fold cost differential
brings to your perception of quality of service.

73's
Richard Clark, KB7QHC

From a casual look at the phone the metal band seems to be a continuous
loop. Its unlikely that there is a physical coupling between it and the
RX/TX, so any tuner or coupling is going to be affected by the hand
grasping it. Since suggestions have been made to hold the phone in a
different place, I would guess that the coupling method is suseptible
to adsorbtion effects and that the hot parts are near the base of the
phone.

FWIW Every mobile phone I've played with has the antenna and coupling
circuitry near the top behind the display.

73's
--
Best Regards:
Baron.

Design Flaw in iPhone 4, Testers Say
 

Baron wrote:
Richard Clark Inscribed thus:

On Mon, 12 Jul 2010 21:54:17 -0500, tom wrote:

On 7/12/2010 9:46 PM, Richard Clark wrote:
The only thing that remains a mystery, for me if for no one else
here,
is the literal specification of the antenna. Google (gasp) fails
me.

73's
Richard Clark, KB7QHC
And that does seem to be the crux of the matter. What is the antenna?
And what does it interact with that's not, be it part of the phone or
part of the user?
Hi Tom,

The antenna is reported as being the metal trim that surrounds the
perimeter of the phone. As that is much too large for the frequencies
involved to be taken literally, there is more to the story that
remains clouded. Maybe I'm wrong....

I think you're right. "Design Flaw" Someone messed up testing big time.

If the loop (or dipole) is suitably matched, it doesn't give much
polarization diversity. Perhaps no phone does anyway.

Aren't cell stations vertically polarised. The one near me is, and one
of the IF's is smack on 144.005 Mhz.

Insofar as being "part of the user," we well know the EM of HTs and
the hand/body contribution. If such were the case, then this would be
an agnostic problem that users of all mobile phones would complain of
(which mildly refutes what the gadget blogs dismissed). On the other
hand, the über-hip, whose complaints are more vocal for their "pain,"
would be outraged at the notion of their simply enjoying the identical
experience of techno-trash. Amazing what a 10 fold cost differential
brings to your perception of quality of service.

73's
Richard Clark, KB7QHC

From a casual look at the phone the metal band seems to be a continuous
loop. Its unlikely that there is a physical coupling between it and the
RX/TX, so any tuner or coupling is going to be affected by the hand
grasping it. Since suggestions have been made to hold the phone in a
different place, I would guess that the coupling method is suseptible
to adsorbtion effects and that the hot parts are near the base of the
phone.

FWIW Every mobile phone I've played with has the antenna and coupling
circuitry near the top behind the display.


Not any more.. recent phones (last several years) put the antenna at the
bottom to reduce the SAR number, since the top of the phone is next to
your head, and the bottom isn't. There's a really good explanation from
a guy who does, oddly, wireless device antenna design consulting..
http://www.antennasys.com/
specifically
http://www.antennasys.com/antennasys...-antennas.html


http://www.anandtech.com/show/3794/t...one-4-review/2 has some
information

Design Flaw in iPhone 4, Testers Say
 

On Tue, 13 Jul 2010 13:51:46 -0700, Jim Lux
wrote:


http://www.anandtech.com/show/3794/t...one-4-review/2 has some
information

Thanx Jim,

Everything Apple didn't want you to know (Antennas, and oddly enough,
a report giving it an A+++ for signal quality).

73's
Richard Clark, KB7QHC