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Default Do you know where we can find the 3 key WiFi specs for the iPad?

In a recent thread, there was speculation on the WiFi specs of
the Apple iPad with respect to similar non-Apple tablets; but,
no proof was provided.

This thread is intended to nail down the 3 key WiFi specs of
the Apple iPad.

To start, I ask of all ...

Do you know where we can find the 3 key WiFi specs for the iPad?
1. WiFi radio transmit power (usually specified in milliwatts or dBm)
2. WiFi radio sensitivity (usually specified in dBm)
3. WiFi antenna gain (usually specified in dBi)
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Default Do you know where we can find the 3 key WiFi specs for the iPad?

On Sat, 1 Mar 2014 13:27:53 -0800, Liam O'Connor wrote:

Do you know where we can find the 3 key WiFi specs for the iPad?
1. WiFi radio transmit power (usually specified in milliwatts or dBm)
2. WiFi radio sensitivity (usually specified in dBm)
3. WiFi antenna gain (usually specified in dBi)


Googling, I found this iPad teardown, which shows the hardwa
http://www.ifixit.com/Teardown/iPad+Wi-Fi+Teardown/2183

The iPad uses a "Broadcom BCM4329XKUBG 802.11n WiFi" board.
http://s1.guide-images.ifixit.com/igi/V6QetUKjFdDsDYga

The WiFi antenna is right behind the Apple logo:
http://d3nevzfk7ii3be.cloudfront.net...WXasqYpDiLQCC3

But, I didn't see the key specs listed.
So, next, I'll look at the FCC teardown.
http://www.ifixit.com/Teardown/iPad+FCC+Teardown/2197
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Default Do you know where we can find the 3 key WiFi specs for the iPad?

On Sat, 1 Mar 2014 13:33:22 -0800, Liam O'Connor wrote:

But, I didn't see the 3 key specs listed.
So, next, I'll look at the FCC teardown.
http://www.ifixit.com/Teardown/iPad+FCC+Teardown/2197


The fcc teardown report didn't contain the 3 key specs,
so, and I'm having trouble downloading the FCC SAR evaluation report:

https://fjallfoss.fcc.gov/prod/oet/f...e_or_pdf=p df
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Default Do you know where we can find the 3 key WiFi specs for the iPad?

On Sat, 1 Mar 2014 13:27:53 -0800, Liam O'Connor
wrote:

In a recent thread, there was speculation on the WiFi specs of
the Apple iPad with respect to similar non-Apple tablets; but,
no proof was provided.


Recent thread where? Article ID please.

This thread is intended to nail down the 3 key WiFi specs of
the Apple iPad.

To start, I ask of all ...

Do you know where we can find the 3 key WiFi specs for the iPad?
1. WiFi radio transmit power (usually specified in milliwatts or dBm)


In the FCC type certification test results. The tx power is somewhat
different for each end of the band and for different modulation nodes
(b/g/n/a). There is no single value for tx power.

For USA:
Model A1219 FCC ID: BCG E2381A
Model A1337 FCC ID: BCG E2328A
Model A1395 FCC ID: BCG A1395
Model A1396 FCC ID: BCG A1396
For the iPad 3:
Wi-Fi Only FCC ID: BCG A1416
Verizon LTE FCC ID: BCG A1403
AT&T LTE FCC ID: BCG A1430
etc...

When the FCC ID web pile stops crashing, plug the FCC ID number into:
http://transition.fcc.gov/oet/ea/fccid/
and you should eventually find the xmit power. I would post some
examples, but as is normal on weekends, the FCC ID site has crashed.

For the iPad 3, nominal 2.4GHz tx output is about 16dBm. For 5GHz,
it's about 17dBm, except in the UNI-1 band, where it's 13.5dBm.

2. WiFi radio sensitivity (usually specified in dBm)


That's not easily measured. The best that can be done is to assume
that it's the same as the sensitivity of the chipset. Most iPads use
a Broadcom BCM43291HKUBC chip, which requires that you request the
data sheet from Broadcom and possibly sign and NDA. Good luck:
https://www.broadcom.com/products/Bluetooth/Bluetooth-RF-Silicon-and-Software-Solutions/BCM4329
Please note that the receive sensitivity is different of each mode
(b/g/n/a) and for each connection speed. Like transmit power, there
is no single value for sensitivity. Sensitivity is usually measured
with a BER (bit error rate tester) and a pile of test equipment. Check
out the various Wi-Fi test equipment vendors for app notes.

Just to make things interesting, the usable sensitivity can be reduced
by external influences, such as your hand on the antenna as in the
iPhone 4. There can also be RFI generated by the processor and
display drivers inside the iPad. Treat the specs as best case.

3. WiFi antenna gain (usually specified in dBi)


The antennas in the various iPad mutations vary in location and type
with model number. For example, the iPad 1 has it behind the Apple
logo, which methinks is a great location.
http://www.cultofmac.com/156848/ipad-3-wi-fi-issues-tested-worst-performance-yet-but-does-it-really-matter/
The iPad 2 has it just to the (rear view) right of the power
connector.
http://cdn.imore.com/sites/imore.com/files/field/image/2012/07/iPad-2-wifi-antenna-caution-area.jpg
On the iPad 3 antenna, the wi-fi antenna is glued to the speaker,
which is not a great idea. It also looks kinda minimal:
http://www.ifixit.com/Guide/iPad+3+4G+Wi-Fi+Antenna+Replacement/8750
See steps 41 thru 43.
On the iPad Air, there are two antennas glued to the inside lower
back. They're the black rectangles with the coax cables in the photo:
http://d3nevzfk7ii3be.cloudfront.net/igi/j1bWSkU3hGUAmpcU.huge

The dual band (2.4/5GHz) antennas are possibly a PIFA (Planar Inverted
F Antenna) type. I haven't torn one apart yet to see what's inside.
It's difficult to determine the gain for such antennas without an NEC
model. This might help
https://discussions.apple.com/thread/4866269
Kinda looks like these numbers came from an NEC modelling program, and
not from field tests.

So, what problem are you trying to solve? Lousy sensitivity perhaps:
https://discussions.apple.com/message/17887360#17887360
(1400 messages). It's apparently a common problem.

--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
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Default Do you know where we can find the 3 key WiFi specs for theiPad?

On Sat, 1 Mar 2014, Jeff Liebermann wrote:

On Sat, 1 Mar 2014 13:27:53 -0800, Liam O'Connor
wrote:

In a recent thread, there was speculation on the WiFi specs of
the Apple iPad with respect to similar non-Apple tablets; but,
no proof was provided.


Recent thread where? Article ID please.

Probably in one of the other two newsgroups. This is the guy who added
..repair to an ongoing thread, and now started this thread crossposted to
three newsgroups, still include .repair.

MIchael


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Default Do you know where we can find the 3 key WiFi specs for the iPad?

In article , Jeff
Liebermann wrote:

When the FCC ID web pile stops crashing, plug the FCC ID number into:
http://transition.fcc.gov/oet/ea/fccid/
and you should eventually find the xmit power. I would post some
examples, but as is normal on weekends, the FCC ID site has crashed.


it's been working fine for me.

the only problem i've had was during the government shutdown when it
was offline.

they could have left the server running during that time. it's not like
anyone sits there and fills the requests as they come in.

....snip...

Just to make things interesting, the usable sensitivity can be reduced
by external influences, such as your hand on the antenna as in the
iPhone 4. There can also be RFI generated by the processor and
display drivers inside the iPad. Treat the specs as best case.


reception on all radios is reduced with one's hand on or near the
antenna, which is why just about every device maker tells you how to
hold it, and not to put your hand near the antenna.

it's not just apple.
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Default Do you know where we can find the 3 key WiFi specs for the iPad?

On Sat, 01 Mar 2014 23:40:57 -0500, nospam
wrote:

In article , Jeff
Liebermann wrote:

When the FCC ID web pile stops crashing, plug the FCC ID number into:
http://transition.fcc.gov/oet/ea/fccid/
and you should eventually find the xmit power. I would post some
examples, but as is normal on weekends, the FCC ID site has crashed.


it's been working fine for me.


The Following Error(s) Occurred While Retrieving The Requested Page:
Date and time of error: Sun Mar 02 00:02:08 EST 2014
Requester's address: 192.168.199.13
Requester's browser type: Mozilla/5.0 (Windows NT 5.1; rv:27.0)
Gecko/20100101 Firefox/27.0
Called from: http://transition.fcc.gov/oet/ea/fccid/
Parameters specified: RequestTimeout=500
Diagnostic information: Error Executing Database Query.
weblogic.common.resourcepool.ResourceDisabledExcep tion: Pool
OETDataSource is Suspended, cannot allocate resources to
applications..
The error occurred on line 26.

the only problem i've had was during the government shutdown when it
was offline.


It belches similar errors almost every weekend when I try it.

they could have left the server running during that time. it's not like
anyone sits there and fills the requests as they come in.


I suspect that there's nobody paying attention to log files and error
messages on weekends.

Just to make things interesting, the usable sensitivity can be reduced
by external influences, such as your hand on the antenna as in the
iPhone 4. There can also be RFI generated by the processor and
display drivers inside the iPad. Treat the specs as best case.


reception on all radios is reduced with one's hand on or near the
antenna, which is why just about every device maker tells you how to
hold it, and not to put your hand near the antenna.

it's not just apple.


Correct. Except that Apple is the worst. I was referring to the
wi-fi performance, which is also affected by hand contact with the
antenna. However, I don't have numbers for wi-fi, just cellular:
http://802.11junk.com/jeffl/cellular/cell-test.htm
That's about 4 years old. Not much has changed. I have some guesses
as to why, but I can't prove it without destroying at least two
iPhones. Hint: To the best of knowledge, Apple iPhone 4 and 5 are
the only devices that use an untuned monopole as an antenna. Even the
iPads don't do that.

--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
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Default Do you know where we can find the 3 key WiFi specs for the iPad?

On Sat, 1 Mar 2014 14:05:27 -0800, Liam O'Connor wrote:

The fcc teardown report didn't contain the 3 key specs,
so, and I'm having trouble downloading the FCC SAR evaluation report:


I will try these suggestions kindly supplied in the other thread:
I wonder if the FCC reports are available to the public?


http://transition.fcc.gov/oet/ea/fccid/

It would be interesting to see what specs iPads iPhones have.


here are some numbers, plus the fcc ids so you can look up all the gory
details:

http://www.revolutionwifi.net/2012/03/ipad-3-wi-fi-specifications.html
https://discussions.apple.com/thread/4866269
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Default Do you know where we can find the 3 key WiFi specs for the iPad?

In article , Jeff
Liebermann wrote:

Just to make things interesting, the usable sensitivity can be reduced
by external influences, such as your hand on the antenna as in the
iPhone 4. There can also be RFI generated by the processor and
display drivers inside the iPad. Treat the specs as best case.


reception on all radios is reduced with one's hand on or near the
antenna, which is why just about every device maker tells you how to
hold it, and not to put your hand near the antenna.

it's not just apple.


Correct. Except that Apple is the worst.


nope. they're about the same as everyone else. a little worse than some
and not as bad as others.

I was referring to the
wi-fi performance, which is also affected by hand contact with the
antenna. However, I don't have numbers for wi-fi, just cellular:
http://802.11junk.com/jeffl/cellular/cell-test.htm
That's about 4 years old. Not much has changed. I have some guesses
as to why, but I can't prove it without destroying at least two
iPhones. Hint: To the best of knowledge, Apple iPhone 4 and 5 are
the only devices that use an untuned monopole as an antenna. Even the
iPads don't do that.


the iphone 4 worked *better* than the 3gs it replaced, with fewer
dropped calls.

most users didn't have a problem with the antenna according to a survey
from changewave. in fact, very few thought it was a serious problem.

apple sold the iphone 4 for three years (and still sells it in some
parts of the world). once the initial hype died down, nobody
complained.

it's the same damned phone. if it really was as screwed up as some
claim, there would be ongoing complaints, and there are not.

other phones have the same issue, if not more so:
http://www.youtube.com/watch?v=zft3-Lwh2bo
http://www.youtube.com/watch?v=c4zbQ3f7H0U

many phones say 'don't hold it wrong'
http://dontholditwrong.tumblr.com/
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Default Do you know where we can find the 3 key WiFi specs for the iPad?

On Sat, 01 Mar 2014 16:19:40 -0800, Jeff Liebermann wrote:

For the iPad 3, nominal 2.4GHz tx output is about 16dBm.
For 5GHz, it's about 17dBm


Hi Jeff,
I haven't seen you on a.i.w all that much lately, but, I knew
you frequented s.e.r more studiously, so, I'm very glad you
stopped by to help us out.

All we want to do is nail down the iPad WiFi specs.

There is speculation that they are substandard (as compared to
similar non-Apple equipment); but let's leave that speculation
out of the factual data for now, and just figure out what it is.

I have a question about what those numbers in the quote are for.

If the transmit "output" is 16dBm at 2.4GHz and 17dBm at 5GHz,
I presume you mean sans an antenna because I don't see the
customary 3dB difference between the two numbers (which would
be entirely antenna related).

If so, the radio transmit power is roughly 40mW at 2.4GHz.
And, at 5GHz, it's roughly 50Mw.

Are my assumptions above about nominal transmit power correct?


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Default Do you know where we can find the 3 key WiFi specs for the iPad?

On Sat, 01 Mar 2014 16:19:40 -0800, Jeff Liebermann wrote:

So, what problem are you trying to solve? Lousy sensitivity perhaps:
https://discussions.apple.com/message/17887360#17887360
(1400 messages). It's apparently a common problem.


Hi Jeff,

In a word, yes.

I recently obtained an iPad for the first time in my life,
and I was shocked (and appalled) over what appears to be
lousy receiver sensitivy (as compared to non-Apple devices
in my very handsat the very same time and place).

I mentioned that in a recent a.m.i thread, where others
refuted my ad hoc observations. A few people said their
reception is just fine, and that I might have a bad unit.

Since I have anecdotal information that some/most/all Apple
devices are weak in radio reception and/or antenna gain, I
was asked to provide the details, which I didn't have.

So, the goal is merely to compare your typical iPad with
your typical non-Apple simimlar device for the three nominal
specs of:

a. Antenna gain (we can pick a single frequency for simplicity)
b. Radio sensitivity (again, we can pick a single frequency)
c. Radio transmit power (at any one frequency should be good enough)
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Default Do you know where we can find the 3 key WiFi specs for the iPad?

On Sun, 02 Mar 2014 00:49:32 -0500, nospam
wrote:

In article , Jeff
Liebermann wrote:

Just to make things interesting, the usable sensitivity can be reduced
by external influences, such as your hand on the antenna as in the
iPhone 4. There can also be RFI generated by the processor and
display drivers inside the iPad. Treat the specs as best case.

reception on all radios is reduced with one's hand on or near the
antenna, which is why just about every device maker tells you how to
hold it, and not to put your hand near the antenna.

it's not just apple.


Correct. Except that Apple is the worst.


nope. they're about the same as everyone else. a little worse than some
and not as bad as others.


I have the numbers from my test at:
http://802.11junk.com/jeffl/cellular/cell-test.htm
What do you have?

Try your phone, whatever it might be. Post the signal strength in
-dbm for holding it normally, holding it with 2 fingers, and holding
it in a death grip covering the antenna.

the iphone 4 worked *better* than the 3gs it replaced, with fewer
dropped calls.


I used an iPhone 3G for about 2 years on Verizon. No dropped calls.
However, my friends with similar phones on AT&T were constantly
dropping calls. Oddly, when the problems with the iPhone 4 appeared
my friend's iPhone 3G's magically stopped dropping calls. AT&T said
they didn't change anything. What happened is that the disconnect
time was extended, so that the system could tolerate extended deep
fades as produced by the antenna grip problem.

most users didn't have a problem with the antenna according to a survey
from changewave. in fact, very few thought it was a serious problem.


Sigh. If you just bought an iPhone and someone asked if you're having
"serious" problems what would you say? I'm in the computer repair biz
and find Apple users rarely admit they have problems unless they are
totally desperate. Instead of asking if they had "serious" problems,
I wonder how the survey would look if they asked "Have you learned to
tolerate the antenna grip problems"?

apple sold the iphone 4 for three years (and still sells it in some
parts of the world). once the initial hype died down, nobody
complained.


Sure. The rubber bumpers sorta work.

it's the same damned phone. if it really was as screwed up as some
claim, there would be ongoing complaints, and there are not.


I see. If there are no complaints, there is no problem. Time for an
old anecdote. Once upon a time, I helped a friend who owned a company
that sold light pens for the PC. Included with each pen were the
usual instructions, drivers, and documentation. After shipping about
2000 light pens, someone casually mentioned that the demo software
crashed. I checked and sure enough, it crashes every time. My guess
is at least 800 users had installed the card, ran the install
software, ran the demo, watched it crash, and said absolutely nothing.
It never ceases to amaze me how much poor quality, bad software, junk
hardware, miserable design, etc the GUM (great unwashed masses) has
learned to tolerate.

Oh, yes. Nobody complains. Here's Google search for "iphone 4
dropped calls" with the date limited to the past month:
https://www.google.com/#q=iphone+4+dropped+calls&tbs=qdr:m
Seems to be quite a few complaints. Instead of nobody complaining,
perhaps the problem is that nobody is listening to the constant
complaints?

other phones have the same issue, if not more so:
http://www.youtube.com/watch?v=zft3-Lwh2bo
http://www.youtube.com/watch?v=c4zbQ3f7H0U


I find it interesting that you picked two videos that measure signal
strength in "bars". Both phones have pages that show signal strength
in -dBm. All I want to know is how many dB does the signal level drop
when the phone is badly gripped.

many phones say 'don't hold it wrong'
http://dontholditwrong.tumblr.com/


Yep. That's part of the wholesale repudiation of responsibility and
litigation avoidance document included with every product these days.

--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
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Default Do you know where we can find the 3 key WiFi specs for the iPad?

On Sat, 1 Mar 2014 21:54:39 -0800, Liam O'Connor
wrote:

If the transmit "output" is 16dBm at 2.4GHz and 17dBm at 5GHz,
I presume you mean sans an antenna because I don't see the
customary 3dB difference between the two numbers (which would
be entirely antenna related).


The 3dB difference in gains between the two bands is pure coincidence.
It can be anything.

If so, the radio transmit power is roughly 40mW at 2.4GHz.
And, at 5GHz, it's roughly 50Mw.


http://www.rapidtables.com/convert/power/dBm_to_mW.htm
16dBm = 40mw
17dBm = 50mw

--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
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Default Do you know where we can find the 3 key WiFi specs for the iPad?

On Sat, 01 Mar 2014 23:13:56 -0800, Jeff Liebermann wrote:

The 3dB difference in gains between the two bands is pure coincidence.
It can be anything.


OK. Maybe I'm mistaken.

In "my" experience, when I buy, say, an 18 inch dish reflector
for a WiFi radio, there always seems to be a 3dB gain in the 5GHz
specifications as compared to the 2.4GHz specifications for
the same power setting of the radio.

I had thought that 3dB doubling of power was due to the inherent
physics behind doubling the frequency from 2.4 to 5 GHz.
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Default Do you know where we can find the 3 key WiFi specs for the iPad?

On Sat, 1 Mar 2014 21:54:39 -0800, Liam O'Connor
wrote:

There is speculation that they are substandard (as compared to
similar non-Apple equipment); but let's leave that speculation
out of the factual data for now, and just figure out what it is.


Which iPad? Model number or FCC ID number please. I don't like
working in the dark.

I don't think you're going to have much luck with converting
specifications to performance expectations. It's much easier to avoid
most of the math and just do a comparison with a known working device.

I suggest you install iPerf/Jperf on your iPad and on a desktop (any
OS).
For IOS:
https://itunes.apple.com/us/app/wifi-perf/id458836095
http://wlanbook.com/wifiperf-iperf3-iperf-3-ios-iphone-ipod-touch-ipad-app/
Android:
https://play.google.com/store/apps/details?id=com.magicandroidapps.iperf
PC (Java front end):
https://code.google.com/p/xjperf/
OS/X
http://wlanbook.com/iperf3-mac-os-snow-leopard-lion-iperf/
Tutorial:
http://openmaniak.com/iperf.php
Scroll to near the bottom for what Jperf looks like.

Setup a fairly fast PC or Mac desktop to act as the iPerf/Jperf
server. Test it with the iPad to see if you can get reasonable TCP
graphs. (don't bother with UDP for now). Play with it until it seems
reliable.

Now for the real test. Dive into the settings for your wireless
router and set it for 802.11g only (or b/g only) and a fixed speed of
54Mbits/sec. No 802.11n, no turbo, and no other speed enhancements.
It is critical that speed is locked to 54Mbits/sec so don't skip that
setting.

If your iPad comes with a case or keyboard, please remove them for the
test. Turn off Bluetooth as it might slow things down.

Start Jperf and start walking away from the wireless router. The
speed should be fairly constant up to about 25ft, where the graph will
likely drop rather quickly. Measure the distance. Now, do the same
thing with other IOS devices, Android devices, and laptops. The idea
is to use the signal strength and thruput while the iPad is sending or
receiving data.

Note that I haven't done this for a while and am not sure exactly what
will happen. I'll try it with my shiny new Galaxy Tab 3 7.0" tomorrow
or sometime next week.

The distances will be approximate, but it should give you a clue as to
the relative ranges of the various devices. You might see strange
results if you do it indoors, but if you put the wireless router in a
window or doorway, and do it outside, you will probably see more
stable numbers.

There are plenty of other things that can also be tested with
iPerf/Jperf but that can come later.

This test won't tell you if the iPad is meeting its own
specifications, but will tell you if it's inferior to other devices or
has a serious range problem.

--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558


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Default Do you know where we can find the 3 key WiFi specs for the iPad?

On Sat, 1 Mar 2014 23:23:48 -0800, Liam O'Connor
wrote:

On Sat, 01 Mar 2014 23:13:56 -0800, Jeff Liebermann wrote:

The 3dB difference in gains between the two bands is pure coincidence.
It can be anything.


OK. Maybe I'm mistaken.

In "my" experience, when I buy, say, an 18 inch dish reflector
for a WiFi radio, there always seems to be a 3dB gain in the 5GHz
specifications as compared to the 2.4GHz specifications for
the same power setting of the radio.

I had thought that 3dB doubling of power was due to the inherent
physics behind doubling the frequency from 2.4 to 5 GHz.


Ok, let's grind the numbers for a dish. The gain of a dish is:

G = Pi^2 * Diameter^2 * aperture_efficiency / wavelength^2

If you multiply the wavelength by 2.4/5.7
the 5.7GHz gain will increase by 1/0.42^2 = 5.7 times.
Converting to dB, that is a gain increase of 7.5 dB.

This assumes that the feed illumination angle and efficiency remain
the same for both 2.4 and 5.7Ghz. That's a tolerable assumption for a
dish. However, it's not for a dual band PIFA antenna, which in this
case according to the specs seems to have about 4.2dB more gain at
5.7GHz than at 2.4GHz.


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On Sat, 1 Mar 2014 22:03:03 -0800, Liam O'Connor
wrote:

b. Radio sensitivity (again, we can pick a single frequency)


Seven years ago, I did this receiver sensitivity chart for various
wi-fi routers:
http://802.11junk.com/jeffl/rx-sens/receiver%20sensitivity.htm
All of the numbers came from the data sheets which amazingly matched
the chip manufacturers numbers almost exactly. That's not going to
help you get the iPad sensitivity, but I thought it might be of some
interest.

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In article , Jeff
Liebermann wrote:

reception on all radios is reduced with one's hand on or near the
antenna, which is why just about every device maker tells you how to
hold it, and not to put your hand near the antenna.

it's not just apple.

Correct. Except that Apple is the worst.


nope. they're about the same as everyone else. a little worse than some
and not as bad as others.


I have the numbers from my test at:
http://802.11junk.com/jeffl/cellular/cell-test.htm
What do you have?

Try your phone, whatever it might be. Post the signal strength in
-dbm for holding it normally, holding it with 2 fingers, and holding
it in a death grip covering the antenna.


i have many phones here, from flip to candybar to iphone to android,
and they all drop in signal strength depending on where i hold it.

the iphone 4 worked *better* than the 3gs it replaced, with fewer
dropped calls.


I used an iPhone 3G for about 2 years on Verizon.


no you didn't.

the iphone 3g is gsm only. there is no cdma.

the iphone was an at&t exclusive until the iphone 4 cdma in early 2011.

No dropped calls.
However, my friends with similar phones on AT&T were constantly
dropping calls.


at&t had a lot of issues, especially in the bay area. there were a lot
of dropped calls well before the iphone 4, as well as ****ty data
speeds. they were overloaded, big time. they didn't expect the iphone
to be as successful as it was.

in fact, at&t was the #1 complaint from iphone users early on.

Oddly, when the problems with the iPhone 4 appeared
my friend's iPhone 3G's magically stopped dropping calls. AT&T said
they didn't change anything. What happened is that the disconnect
time was extended, so that the system could tolerate extended deep
fades as produced by the antenna grip problem.


what proof do you have that's what they did, when they said they didn't
do anything?

and at the end of the day, the user doesn't care *why* a call didn't
drop, only that it didn't.

most users didn't have a problem with the antenna according to a survey
from changewave. in fact, very few thought it was a serious problem.


Sigh. If you just bought an iPhone and someone asked if you're having
"serious" problems what would you say?


depends if i'm having serious problems or not.

changewave is in the business of surveys. they ask a statistically
valid sample. the majority (by a lot) didn't have a problem.

I'm in the computer repair biz
and find Apple users rarely admit they have problems unless they are
totally desperate. Instead of asking if they had "serious" problems,
I wonder how the survey would look if they asked "Have you learned to
tolerate the antenna grip problems"?


in fact, they did ask about that, and not that many said it was
serious. i need to find the actual survey though for specifics.

apple sold the iphone 4 for three years (and still sells it in some
parts of the world). once the initial hype died down, nobody
complained.


Sure. The rubber bumpers sorta work.


those help but not required. that was mostly to get the whiners to stop
whining.

note that after the free bumper offer ended, there weren't very many
additional complaints.

it's the same damned phone. if it really was as screwed up as some
claim, there would be ongoing complaints, and there are not.


I see. If there are no complaints, there is no problem.


pretty much.

if it isn't affecting anyone, then how is it even a problem?

Time for an
old anecdote. Once upon a time, I helped a friend who owned a company
that sold light pens for the PC. Included with each pen were the
usual instructions, drivers, and documentation. After shipping about
2000 light pens, someone casually mentioned that the demo software
crashed. I checked and sure enough, it crashes every time. My guess
is at least 800 users had installed the card, ran the install
software, ran the demo, watched it crash, and said absolutely nothing.
It never ceases to amaze me how much poor quality, bad software, junk
hardware, miserable design, etc the GUM (great unwashed masses) has
learned to tolerate.


interesting story, but i don't know what that has to do with anything.

Oh, yes. Nobody complains. Here's Google search for "iphone 4
dropped calls" with the date limited to the past month:
https://www.google.com/#q=iphone+4+dropped+calls&tbs=qdr:m
Seems to be quite a few complaints. Instead of nobody complaining,
perhaps the problem is that nobody is listening to the constant
complaints?


apple has likely sold at least 100 million iphone 4 over the past 3+
years (they don't give specific model breakdowns).

they sold 51 million iphones last quarter *alone*.

the reality is that most users did not find it to be a problem. at all.

however, the number is never going to be zero. if you touch the
antenna, the signal strength will drop, just like any phone.

people like to complain.

other phones have the same issue, if not more so:
http://www.youtube.com/watch?v=zft3-Lwh2bo
http://www.youtube.com/watch?v=c4zbQ3f7H0U


I find it interesting that you picked two videos that measure signal
strength in "bars". Both phones have pages that show signal strength
in -dBm. All I want to know is how many dB does the signal level drop
when the phone is badly gripped.


i picked a couple of videos that show the effect of 'holding it wrong'.

many phones say 'don't hold it wrong'
http://dontholditwrong.tumblr.com/


Yep. That's part of the wholesale repudiation of responsibility and
litigation avoidance document included with every product these days.


or it's part of actual effects.

i have a flip phone where the instructions say how to hold it, and if i
hold it the way it says not to, the signal strength drops.
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On Sun, 02 Mar 2014 00:06:47 -0800, Jeff Liebermann wrote:

Converting to dB, that is a gain increase of 7.5 dB.


Wow. That's six times the power, not just doubling.

I officially will give up on my prior assumption
that the power gain at 5GHz was twice that at 2.4 GHz.

It's actually 5.62 times the power!

Thanks for explaining.

The important takeaway is that the iPad antenna has
4.2dB more gain at 5.7GHz than at 2.4GHz (which means
the iPad transmits 2.6 times as much power at 5.7GHz
as it does at 2.4GHz).

Note: My conversion of dB to power factor are from he
http://www.sengpielaudio.com/calculator-db.htm
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On Sun, 2 Mar 2014 08:12:31 +0000 (UTC), Lewis
wrote:

In message
Jeff Liebermann wrote:
I used an iPhone 3G for about 2 years on Verizon.


No you didn't. The iPhone 3G did not work on Verizon. Neither did the
iPhone 3GS. Neither did the initial iPhone 4.


Oops. My apologies and my faulty memory (again).

Starting in about 2006, I used a XV6700 on Verizon. Not the best
audio or range, but no disconnects:
http://802.11junk.com/jeffl/xv6700/XV6700.htm
Starting in about 2009, I used an iPhone 3G on AT&T for only about a
week after which I discontinued the service due to poor coverage in my
mountain area. For the next year or so, I went through a variety of
used phones on Verizon. Since the iPhone 3G was mine, I carried it
around as a PDA for about 2 years after pulling the plug with AT&T.
After that, I retired the iPhone 3G and switched to a Droid X and
later a Droid X2. For cellular voice, I use, an old LG VX8300 phone
on Verizon.

The reduction in dropped calls on my friends AT&T iPhone 3G's was
quite real.




--
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150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558


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On Sat, 01 Mar 2014 23:45:24 -0800, Jeff Liebermann wrote:

This test won't tell you if the iPad is meeting its own
specifications, but will tell you if it's inferior to other devices or
has a serious range problem.


This is an excellent idea!
Thanks!
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In article , Jeff
Liebermann wrote:

The reduction in dropped calls on my friends AT&T iPhone 3G's was
quite real.


they probably added capacity, which they said they would be doing
because it was so horribly overloaded.
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Default Do you know where we can find the 3 key WiFi specs for the iPad?

On Sun, 02 Mar 2014 00:15:50 -0800, Jeff Liebermann wrote:

All of the numbers came from the data sheets which amazingly matched
the chip manufacturers numbers almost exactly.


Hi Jeff,

That's pretty interesting, because, well, um, I had assumed
that they almost always lie when it comes to specifications.

The WiFi chip found in this iPad teardown
http://www.ifixit.com/Teardown/iPad+Wi-Fi+Teardown/2183

Is the Broadcom BCM4329:
http://www.broadcom.com/products/Blu...utions/BCM4329

Googling for the specs for that broadcom chip, I "think" I found
them on page 6 of this document:
http://www.lairdtech.com/WorkArea/Do...?id=2147486570

Do those specs look reasonable for that chip?
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On Sun, 02 Mar 2014 03:24:41 -0500, nospam
wrote:

changewave is in the business of surveys. they ask a statistically
valid sample. the majority (by a lot) didn't have a problem.

I'm in the computer repair biz
and find Apple users rarely admit they have problems unless they are
totally desperate. Instead of asking if they had "serious" problems,
I wonder how the survey would look if they asked "Have you learned to
tolerate the antenna grip problems"?


in fact, they did ask about that, and not that many said it was
serious. i need to find the actual survey though for specifics.


http://investorplace.com/2010/08/apple-inc-iphone-4-survey-att-verizon/
See the red bar graph showing iPhone 4 dislikes. 24% listed "antenna
issues" as what they "most dislike" about the iPhone 4. What someone
dislikes the most is a great way of reducing the incidence of lesser
complaints. For example, users were given a choice of "most dislike"
of requiring using the AT&T network, and coverage, speed, and of the
quality of the AT&T network. The result was 27% and 24% respectively.
What this did was effectively split the complaints about AT&T roughly
in half. If they had only offered AT&T complaints as a single "most
dislike" choice, the combined total of 51% would have indicated that
at least half the users were not thrilled with AT&T. Similarly, the
participants were given the choice of "dropped calls" and "antenna
issues" again effectively splitting the complaints. If I assume that
all dropped calls were precipitated by the antenna problem (not system
overload), then at least 47% were having problems. If they had asked
"Which of the following do you dislike about the iPhone and about
AT&T. Pick all that apply", it would have been a very different
survey.

Of course, there's something wrong with the numbers anyway, as the
total of the percentages adds up to 129% instead of 100%.

The article claims:
To gauge the impact of the antenna obstruction issue, we
asked iPhone 4 owners to tell us how big of a problem it
was for them. Nearly two-thirds reported they Haven’t
Experienced Any Problem and another 14% reported it
Wasn’t Much of a Problem. However one-in-five did report
it was Somewhat of a Problem (14%) or a Very Big Problem (7%).
So, 14+14+7 = 35% of the users were having a problem. I guess Apple
has such a large customer base, that it can afford to ignore 1/3 of
it's early adopters.

Full disclosures. I used to craft such surveys in the late 1980's but
haven't done much since then. I would be interested in seeing the
original survey. They usually charge for reports:
http://changewaveresearch.com

if it isn't affecting anyone, then how is it even a problem?


For every customer that actually calls tech support with a real
problem, it can be assumed that there is a fairly large number of
users that simply didn't bother to call. I've worked on a few
products that had this problem. We didn't know that something was
wrong until one customer made considerable noise at a trade show,
followed by plenty of "me too" complaints. Kinda like priming the
pump. Unfortunately, it's quite common to run a business these days
on the basis of no complaint = no problem. The result is that some
brilliant manager decides that it's easier to discourage complainers
than it is to fix the product. I wrote this about 20 years ago in
honor of such brilliance:
http://members.cruzio.com/~jeffl/poetry/support.htm

More examples of products that don't work, and few or nobody
complains:
http://www.designnews.com/archives.asp?section_id=1367&dfpPParams=bid_240&df pLayout=siteInfo

interesting story, but i don't know what that has to do with anything.


It demonstrates that customer complaints and product defects are not
directly connected. It is quite possible to have a problem, and
nobody complain, as I found out. I can supply other examples of this
if you are not convinced.

apple has likely sold at least 100 million iphone 4 over the past 3+
years (they don't give specific model breakdowns).
they sold 51 million iphones last quarter *alone*.
the reality is that most users did not find it to be a problem. at all.


True. iPhones are not the only products that sell well but have
defects. I see them all the time in the computer biz. For example,
Dell was (allegedly) knowingly selling computers that had defective
electrolytic capacitors known to bulge, leak, and fail in a fairly
short time. Various laptop vendors did much the same with lousy BGA
soldering (and blamed on bad Nvidia chips). They sold quite nicely,
even during the various class action suits and settlements which
provided the only way consumers even knew that there was a problem.

Perception is everything, and the perception of Apple products is
truly impressive.

however, the number is never going to be zero. if you touch the
antenna, the signal strength will drop, just like any phone.


They drop by differing amounts, measured in dB. Did you measure the
signal levels as I suggested in my previous message? I have a mess of
phones in the office that I can measure on Monday or Tues. If you
need help getting into the test mode:
http://www.wilsonelectronics.com/uploads/docs/FieldTestModes06142010%20wilson004.pdf

people like to complain.


Some people do, but most don't. They simply don't consider the effort
necessary to file a proper complaint worthwhile. Also, many companies
have no mechanism for complaints. For example, about 4(?) years ago,
I had a firmware update failure that trashed an Apple aluminum
Bluetooth keyboard. The installer would not let me go back a version,
not let me reinstall, and there was no later version. I asked for
help on various forums and to various email addresses with little
result. When I changed my questions to complaints, my postings were
deleted from the Apple forum and my account locked.

other phones have the same issue, if not more so:
http://www.youtube.com/watch?v=zft3-Lwh2bo
http://www.youtube.com/watch?v=c4zbQ3f7H0U


I find it interesting that you picked two videos that measure signal
strength in "bars". Both phones have pages that show signal strength
in -dBm. All I want to know is how many dB does the signal level drop
when the phone is badly gripped.


i picked a couple of videos that show the effect of 'holding it wrong'.


I saw little in the way of an effect except to see 1 or 2 bars go to
zero. No dropped calls. I have several phones that will successfully
make calls with no bars showing. I want to see the change in signal
level in dBm before and after.

i have a flip phone where the instructions say how to hold it, and if i
hold it the way it says not to, the signal strength drops.


It's still not sinking in. Go to:
http://802.11junk.com/jeffl/cellular/cell-test.htm
All the ordinary cell phones lost signal when the antenna was covered.
Most lost 5 to 8 dB in signal, which is considerable, but not fatal in
moderate signal areas. The worst was 12dB. However, the iPhone 4
lost between 19.8dB and 24.6dB which is enormous, huge, monstrous, and
full able to create a dropout. When I did the tests, we didn't have
the iPhone 4 rubber protectors available, but I can test those when I
have time and add them to the table.

To put the numbers in perspective 5 to 8dB is about 3.2 to 6.3 times.
The iPhone 4 19.8dB to 24.6dB is 95.5 to 288 times drop in signal.
That's like trying to operate with 1/100 to 1/200 of the normal signal
level.

Now do you understand the problem?

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150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
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On Sun, 02 Mar 2014 03:47:51 -0500, nospam
wrote:

In article , Jeff
Liebermann wrote:

The reduction in dropped calls on my friends AT&T iPhone 3G's was
quite real.


they probably added capacity, which they said they would be doing
because it was so horribly overloaded.


I used to track cell sites in the Santa Cruz county area. This is a
really old (2003). I have some spreadsheets and maps with current
cell site locations and capabilities:
http://802.11junk.com/cellular/index.html
The plan was to make an overlay of the coverage areas by vendor, but
that ended when I landed in the hospital for some major surgery. This
is the only map that I managed to do at the time:
http://802.11junk.com/cellular/jeffl/SVLY-PGE/index.html
See map at bottom of page. Since then, the coverage maps produced by
Radio-Mobile have been considerably better:
http://802.11junk.com/jeffl/coverage/VZW-water-plant/850Mhz-2watts-39dBu.jpg
http://802.11junk.com/jeffl/coverage/Boulder-Creek-Cellular/850Mhz-1watt-16dbi-15meters-3D.jpg

At the time (about 2010) there had been some growth in the AT&T system
in the downtown areas and along the major highways. It was not
spectacular. In the mountains, where I live, there has been no
changes in the AT&T system since about 2001. The biggest build was
the shared DAS system at the local university (UCSC). The sites are
at the telco CO's, on a few local hills, 2 small sites, and nothing
more. I can't find my spreadsheet with the locations or I would be
more specific. I think (not sure) that all 3 of my iPhone using
friends were in moderate signal areas, where they would not be
significantly affected by additional cell sites, but would be affected
by additional users.

2AM. Enough for tonite...

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Santa Cruz CA 95060 http://802.11junk.com
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On Sun, 2 Mar 2014 00:51:03 -0800, Liam O'Connor
wrote:

The WiFi chip found in this iPad teardown
http://www.ifixit.com/Teardown/iPad+Wi-Fi+Teardown/2183

Is the Broadcom BCM4329:
http://www.broadcom.com/products/Blu...utions/BCM4329

Googling for the specs for that broadcom chip, I "think" I found
them on page 6 of this document:
http://www.lairdtech.com/WorkArea/Do...?id=2147486570

Do those specs look reasonable for that chip?


No. The problem is that the module is using an XM2400LT for a 2.4Ghz
receiver preamp, and a SKY65404 rx preamp, and an RTC6651 tx power amp
on 5.7GHz. See Pg 5, Fig 1, in the Lairdtech document. Because the
iPad is NOT using any of these additional chips, all the numbers will
be different.

WHICH MODEL IPAD DO YOU HAVE? FCC ID or APPLE MODEL NUMBER.

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Santa Cruz CA 95060 http://802.11junk.com
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Default Do you know where we can find the 3 key WiFi specs for the iPad?

In article , Jeff
Liebermann wrote:


The article claims:
To gauge the impact of the antenna obstruction issue, we
asked iPhone 4 owners to tell us how big of a problem it
was for them. Nearly two-thirds reported they Haven’t
Experienced Any Problem and another 14% reported it
Wasn’t Much of a Problem. However one-in-five did report
it was Somewhat of a Problem (14%) or a Very Big Problem (7%).
So, 14+14+7 = 35% of the users were having a problem. I guess Apple
has such a large customer base, that it can afford to ignore 1/3 of
it's early adopters.


only 7% had a major problem. that's very low, just as i said.

'nearly two-thirds reported they haven't experienced any problem'.
that's a lot.

it also means the entire thing was overblown. most people did not find
it to be a problem *at all*.

add in the 14% who said it wasn't much of a problem and you have almost
80% who are either not impacted at all or only slightly. almost 80% !!!


apple has likely sold at least 100 million iphone 4 over the past 3+
years (they don't give specific model breakdowns).
they sold 51 million iphones last quarter *alone*.
the reality is that most users did not find it to be a problem. at all.


True. iPhones are not the only products that sell well but have
defects. I see them all the time in the computer biz. For example,
Dell was (allegedly) knowingly selling computers that had defective
electrolytic capacitors known to bulge, leak, and fail in a fairly
short time. Various laptop vendors did much the same with lousy BGA
soldering (and blamed on bad Nvidia chips). They sold quite nicely,
even during the various class action suits and settlements which
provided the only way consumers even knew that there was a problem.


the capacitors were not dell's fault. dell bought what they thought
were good capacitors, as did many other companies, and they turned out
to be defective. a lot of companies were affected, including apple.

the nvidia chip delamination issue also affected many companies,
including apple, who issued an extended repair program because of it.

and users found out the hard way, because their products ceased to
function.

Perception is everything, and the perception of Apple products is
truly impressive.


not really.

however, the number is never going to be zero. if you touch the
antenna, the signal strength will drop, just like any phone.


They drop by differing amounts, measured in dB. Did you measure the
signal levels as I suggested in my previous message? I have a mess of
phones in the office that I can measure on Monday or Tues. If you
need help getting into the test mode:

http://www.wilsonelectronics.com/upl...42010%20wilson
004.pdf


what matters is does the phone work in normal day to day operation and
can the user make and receive calls without dropping and do whatever
tasks they want to do.

it does, and they can.

people like to complain.


Some people do, but most don't. They simply don't consider the effort
necessary to file a proper complaint worthwhile.


that's a formal complaint.

you said there were a lot of hits on google. that's *not* a formal
complaint.

it takes almost no effort to post on a forum that a product isn't
working properly or there's some other problem with it (even if it's
minor), the user hates the product etc. type up a rant, and a few
clicks later it's posted for all to see.

it's very rare to see people post that they like something. it happens,
but not as much as complaints.

and this isn't just tech. people complain about everything more than
they do praise. it's human nature.

Also, many companies
have no mechanism for complaints. For example, about 4(?) years ago,
I had a firmware update failure that trashed an Apple aluminum
Bluetooth keyboard. The installer would not let me go back a version,
not let me reinstall, and there was no later version. I asked for
help on various forums and to various email addresses with little
result. When I changed my questions to complaints, my postings were
deleted from the Apple forum and my account locked.


apple has mechanisms for complaints. did you avail yourself of it?

if you took the bluetooth keyboard to an apple store, they would have
fixed it or replaced it.

i have a flip phone where the instructions say how to hold it, and if i
hold it the way it says not to, the signal strength drops.


It's still not sinking in. Go to:
http://802.11junk.com/jeffl/cellular/cell-test.htm
All the ordinary cell phones lost signal when the antenna was covered.


exactly my point. all phones are affected.

that includes the iphone 4. it's no different.

physics is physics.
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nospam wrote:

In article , Jeff
Liebermann wrote:


The article claims:
To gauge the impact of the antenna obstruction issue, we
asked iPhone 4 owners to tell us how big of a problem it
was for them. Nearly two-thirds reported they Haven’t
Experienced Any Problem and another 14% reported it
Wasn’t Much of a Problem. However one-in-five did report
it was Somewhat of a Problem (14%) or a Very Big Problem (7%).
So, 14+14+7 = 35% of the users were having a problem. I guess Apple
has such a large customer base, that it can afford to ignore 1/3 of
it's early adopters.


only 7% had a major problem. that's very low, just as i said.



7% is totally unacceptable. .7% is ridiculous and .07% is still too
high. On the other hand, some people would defend a burning bag of dog
**** as top quality and flawless.

How would you feel if the brakes on your car only worked 93% of the
time? The electricity to your home?


I own a couple Apple computers. I use them for doorstops. They can't
even do that rigt. most of the time.

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Default Do you know where we can find the 3 key WiFi specs for the iPad?

On Sun, 02 Mar 2014 02:15:13 -0800, Jeff Liebermann wrote:

Because the
iPad is NOT using any of these additional chips, all the numbers will
be different.

WHICH MODEL IPAD DO YOU HAVE? FCC ID or APPLE MODEL NUMBER.


Hi Jeff,
Thanks for that advice.
I always appreciate your help.

If I go to my settings in the iPad Air, I find the following:
Settings-General-Software Update = iOS 7.0.6
Settings-General-About-Version = 7.0.6 (11B651)
Settings-General-About-Carrier = T-Mobile 15.5
Settings-General-About-Model = MF534LL/A

Hmmmmmm..... I was expecting a different model number.

Getting out a (real) magnifying glass, I see on the back bottom:
Model A1475 FCC ID: BCGA1475 IC: 579C-A1475
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Default Do you know where we can find the 3 key WiFi specs for the iPad?

In article , Michael A.
Terrell wrote:

only 7% had a major problem. that's very low, just as i said.


7% is totally unacceptable. .7% is ridiculous and .07% is still too
high. On the other hand, some people would defend a burning bag of dog
**** as top quality and flawless.


troll.

first of all, no product has a 0.07% failure rate. that's just not
realistic.

second of all, the proper comparison is with other similar phones, not
zero, and you'll see it's not significantly different.

all cellphones have the same problem to a certain extent, and in some
cases, it's worse with others than it is for an iphone.

How would you feel if the brakes on your car only worked 93% of the
time? The electricity to your home?


i've had to repair the brakes twice in the past 4 years, once on each
of two cars.

the power goes out a few times a year typically, and was flickering a
couple of weeks ago but didn't go off completely. a couple of years ago
after a big storm, it was off for 2 days.

it sucks when it happens but nothing is perfect.

not that either one is relevant. if the signal strength drops a little,
it's not a big deal.

I own a couple Apple computers. I use them for doorstops. They can't
even do that rigt. most of the time.


then computers are far too complicated for you.


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Default Do you know where we can find the 3 key WiFi specs for the iPad?

On Sun, 2 Mar 2014 13:51:09 -0800, Liam O'Connor
wrote:

Getting out a (real) magnifying glass, I see on the back bottom:
Model A1475 FCC ID: BCGA1475 IC: 579C-A1475


That would be an iPad Air with both Wi-Fi and Cellular:
http://everymac.com/ultimate-mac-lookup/?search_keywords=A1475

Model = MF534LL/A


That would be the 64GB model on T-Mobile:
http://everymac.com/systems/apple/ipad/specs/apple-ipad-air-1st-gen-a1475-wi-fi-cellular-lte-specs.html


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Default Do you know where we can find the 3 key WiFi specs for the iPad?

On Sun, 02 Mar 2014 19:33:57 -0800, Jeff Liebermann wrote:

Model A1475 FCC ID: BCGA1475 IC: 579C-A1475

That would be an iPad Air with both Wi-Fi and Cellular:
That would be the 64GB model on T-Mobile:
Plug the FCC ID number into:
http://transition.fcc.gov/oet/ea/fccid/


Hi Jeff,

As per your suggestion, I plugged the FCC ID into:
http://transition.fcc.gov/oet/ea/fccid/

As Grantee Code (First three or five characters of FCCID):
BCG
And as Product Code (Remaining characters of FCCID):
A1475

With the result being the cryptic error:
Date and time of error: Sun Mar 02 23:00:54 EST 2014
Requester's address: 192.168.199.13
Requester's browser type: Mozilla/5.0 (Windows NT 5.1; rv:27.0)
Gecko/20100101 Firefox/27.0
Called from: http://transition.fcc.gov/oet/ea/fccid/
Parameters specified: RequestTimeout=500
Diagnostic information: Error Executing Database Query.
weblogic.common.resourcepool.ResourceDisabledExcep tion: Pool OETDataSource
is Suspended, cannot allocate resources to applications..
The error occurred on line 26.
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Default Do you know where we can find the 3 key WiFi specs for the iPad?

On Sun, 2 Mar 2014 19:56:07 -0800, Liam O'Connor
wrote:

As per your suggestion,


That makes it my fault.

I plugged the FCC ID into:
http://transition.fcc.gov/oet/ea/fccid/


As Grantee Code (First three or five characters of FCCID):
BCG
And as Product Code (Remaining characters of FCCID):
A1475

(...)
The error occurred on line 26.


Yep, that's exactly what I got on 2 machines and one tablet. I
mentioned the problem in one of my rants yesterday. It seems that
almost every weekend, the FCC ID lookup site goes down with some kind
of database error. Oddly, it's not always the same error. It only
seems to happen on weekends, when there is probably nobody looking at
error messages and log files. It will be back sometime on Monday.

--
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Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
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On Sun, 02 Mar 2014 20:05:07 -0800, Jeff Liebermann wrote:

As per your suggestion,


That makes it my fault.


Ooops. I'm sorry if it came off that way.
I know you had already said it often doesn't work.
I'll wait for them to fix it and try again tomorrow.

It's NOT your fault!
You gave good advice!
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nospam wrote:

In article , Michael A.
Terrell wrote:

only 7% had a major problem. that's very low, just as i said.


7% is totally unacceptable. .7% is ridiculous and .07% is still too
high. On the other hand, some people would defend a burning bag of dog
**** as top quality and flawless.


troll.



Moron.


first of all, no product has a 0.07% failure rate. that's just not
realistic.



Disprove it. http://en.wikipedia.org/wiki/Six_Sigma


--
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On Sun, 2 Mar 2014 21:30:29 -0800, Liam O'Connor
wrote:

It's NOT your fault!


It must be someone's fault. The first step to solving a problem is to
blame someone. In other words, it's not going to get fixed without
first assigning the blame. It's generally considered a bad idea
blaming anyone involved in fixing the problem and blaming yourself is
equally counterproductive. It's considered traditional to blame the
person who notices the problem, but that won't work here. Therefore,
I suggest you find suitable culprit, scapegoat, sacrificial victim,
innocent bistander, or consultant to blame.

In the past, when I complained about the non-availability of the site
on weekends, I received the usual "site is down for upgrades" excuse.
I just noticed that it's now fairly close to the official policy of
crashing the site Saturday at 10PM thru Sunday at 6AM EST.
http://www.fcc.gov/encyclopedia/fcc-website-availability

As of:
Mon Mar 03 11:41:50 EST 2014
the FCC ID web pile is still down. Hmmm.... 3 hrs late so far.
Perhaps nobody complained and the (outsourced) admins didn't notice?
http://transition.fcc.gov/oet/ea/fccid/
Enter BCG A1475, search, and click on the "Please report this error to
FCC OET Systems Support" link to send eashelp a reminder. It
automagically includes the error message making it quite easy to
complain.

"Pool OETDataSource is Suspended, cannot allocate..."
I was wondering the meaning of that SQL error message. I think I
found the "suspended pool".
http://www.businessinsider.com/the-suspended-pool-at-a-shanghai-holiday-inn-looks-pretty-freaky-2012-8
Hmmm...

--
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Default Do you know where we can find the 3 key WiFi specs for the iPad?

On Mon, 03 Mar 2014 08:49:26 -0800, Jeff Liebermann
wrote:

As of:
Mon Mar 03 11:41:50 EST 2014
the FCC ID web pile is still down. Hmmm.... 3 hrs late so far.
Perhaps nobody complained and the (outsourced) admins didn't notice?
http://transition.fcc.gov/oet/ea/fccid/
Enter BCG A1475, search, and click on the "Please report this error to
FCC OET Systems Support" link to send eashelp a reminder. It
automagically includes the error message making it quite easy to
complain.


Well, that didn't work. I just got this back from the site:

is no longer an active or
monitored mailbox.

For help resolving issues associated with using the Equipment
Authorization System (EAS), please go to
http://www.fcc.gov/labhelp
and select submit an Inquiry. In the First Category Field, Select
"Administrative Requirements", and include in the subject field
"EAS Help". Please clearly describe your issue in the "enter
inquiry field". After you select submit, you will be permitted
to add attachments. For a faster response please provide PDF
or JPEG of screen images of the error message and the web page
preceding the error message showing all content including the URLs.

Like I said, complaining takes too much effort to be worthwhile.
FCC ID lookup is still dead. Yawn...
--
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Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
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Jeff Liebermann (for it is he) wrote:

innocent bistander


Is a 'bistander' one who, er, prefers to watch?

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On Mon, 03 Mar 2014 21:23:01 +0000, alexd
wrote:

Jeff Liebermann (for it is he) wrote:
innocent bistander


Is a 'bistander' one who, er, prefers to watch?


It would probably help if I had spelled it correctly. That's the
correct US definition, but I had the spelling wrong:
http://dictionary.reference.com/browse/bystander



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