Occam's razor, the bumper, and the iPhone 4 - A theory...

Discussion in 'iPhone' started by br0adband, Jun 28, 2010.

  1. br0adband macrumors 6502a


    Aug 29, 2006
    Ok, this is something I've been thinking about the past few days since I acquired my iPhone 4 (I didn't buy it myself; it was a gift to me but it's mine nonetheless, I own an iPhone 4). My experience(s) have been somewhat summarized at length in the post you can find in the link in my sig, if you care to read it, and an update was added in another post (linked from that one) where someone "demanded" that I stand directly under a cell site and do the same testing, which I did and ended up with effectively the same results. I won't rehash all that in this post, this one is all new and something I'd like people to consider.

    This is going to be a VERY long post, so I hope you'll bear with me as I explain my thoughts and how I believe things are working out.

    If not, you're free to move along - honestly I'd even go so far as to ask that if you don't own an iPhone 4 move along and don't even bother. If you do own an iPhone 4 I welcome discussion whether you are having problems - any problems at all - or not. It's the people that don't own the phone(s) that will cause the most trouble with their posts, of that I'm quite certain, if they choose to post.

    Having said there, here's what I'm thinking:

    If you've ever seen the movie "Contact" with Jodie Foster, etc, based on the Carl Sagan novel of the same name, you'll probably remember them making several scenes that focus around a scientific principle/theory known as "Occam's razor" and it's basically put in this way:

    "The simplest explanation is tends to be the correct one." (or words to that effect as it is expressed in many different forms including the real actual untouched version which says: "Entities must not be multiplied beyond necessity"

    If you haven't seen the movie, and to make a long story short here's how it works out (movie has been around for a long time so don't flame me as spoiling it if you haven't seen it):

    Girl likes astronomy, makes it her life's focus. She's an outsider, traveling her own path, stepping on the toes of "the establishment" by focusing on listening for the existence of life beyond our planet. Everyone thinks she's a nutcase but they tolerate her, up to a point after which she and a few people loyal to her break away from that establishment. Her research continues until a fateful day when she - she herself - detects a signal coming from another part of our galaxy, and with the help of those loyal to her announce it to the world.

    She gets in trouble for it, of course, but buried deep inside the signal itself lay coded plans for building "a machine" that nobody on earth can even fathom the function of. Speculation suggests it's some kind of transport and it's decided that it'll be built. It is, but some religious nutcase with a vest-bomb destroys it. Luckily, because governments always get good deals and can build two for twice the price (a line from the movie, actually), and another machine is already fully built and ready to go, and they want her to be the traveler and of course she agrees.

    Big hoopla, big lightning storms, etc, the machine works, and it opens a wormhole from the inside of the machine directly to where the signal originated: some planet in the Vega star system/cluster/etc. She's there for what to her is about 18 hours, has a conversation of sorts with some type of intelligent life form, and then is returned to earth to the exact spot, pretty much the same instant, that she left - at least from the perspective of those on earth.

    She's touted as a loon, insane, that perhaps the machine's function wrecked her brain to the point where all this was made up from scratch, her fantasy, and she tricked the entire world into believing it all. All she's got to offer to them is her word, and nothing more. When she's brought before Congress to testify, she has no proof - only her word - and still nothing more. Absolutely nothing consequential or concrete except her own experience which unfortunately is dismissed as the crazed rantings of someone perpetrating a fraud.

    Which leads me to this theory, sorry. ;)

    Occam's razor states that the simplest explanation is usually the correct one, and with respect to the bumper - the only one of it's kind as no one else is manufacturing such a "case" for the iPhone 4, at least not yet as of this post - and the iPhone 4 with what is now the well known defects, issues, problems, etc (whatever you wish to call them), I'd like to offer my thinking, some of which is culled from an earlier post I made and re-presented here with as the guts of the working theory.

    Here's what I believe as of right now:

    - That the issue(s) people are noticing are indicative of a design flaw
    - That Apple discovered it way too late into the prototyping phase (pre-fabrication of the actual product, but prototypes were still in testing)
    - That because of such a late discovery they couldn't really do much about it and needed a solution to prevent the primary cause of the signal degradation noted: skin-on-metal contact
    - That the working theory is that they did almost all their testing with iPhone 4 prototypes inside cases to mask them and protect it from prying eyes which precluded them from skin-on-metal contact during all that testing
    - That at some point the device would have had to be removed from the fake case/mask/etc and actually held in someone's hand (field trials, perhaps, who knows)
    - That at that time the discovery was made that signal reception and degradation was occurring in degrees that couldn't be accounted for simply because "we're pretty far from a cell site."
    - That someone with some common sense put two and two together and realized that considering they're dealing with microwave energy transmission, skin-on-metal contact is wicking away that energy in quantities the phone can't adapt to quickly enough (the software issue) to recover/maintain given levels of service
    - That a solution was desperately required since the phone was practically done by that point and they couldn't just scrap the entire process and design
    - The solution presented itself in the form of the bumper that was quick to create, quick to manufacture (make a mold, pour in some rubber, done), cheap as hell, deadly efficient by design, and practically - note: practically solves the skin-on-metal potential 100%

    Now, consider this before you go any further: cellular telephones operate on many different frequencies in their assigned band plans as set by the FCC (here in the US) and whatever regulatory agencies around the world that are responsible for such frequency allocations in their respective countries. The one thing they all share in common is that those frequencies all sit within what's considered to be the microwave range, yes, just like the ones in your microwave oven with one big difference:

    They're thousands if not millions of times less powerful and so are nowhere near as "damaging" to organic tissue as the output from any given cellular phone on the market today, even the iPhone 4. The key here is organic tissue, which includes the skin of our bodies (and our bodies as a whole). Microwave energy does lots of interesting things for many interesting reasons, but when it comes into contact with organic tissue, it really gets interesting. Note I am saying direct physical contact meaning by touching an antenna aka a resonator since an antenna, when fed a specific level of energy at a specific frequency actually vibrates at that frequency which is how radio waves are radiated - radio, radiated, it all works together, get it?

    There's one basic rule of microwave radio transmission, first and foremost (at least in my education which is still ongoing but I've been working with radio communications equipment for 30+ years now, pretty much daily) and that rule is:

    You don't touch microwave antennas, for any reason, ever.

    And by "touch" I do mean precisely that, touching the antenna with organic material, and even more precisely with human hands, palms, fingers, fingertips, etc. You never touch a microwave antenna with your body or any part of it. Why? Well, to make it really simple: because organic tissue loves microwave energy, basically. Organic tissue absorbs microwave energy like a fat man sopping up gravy with a biscuit (disclaimer: I'm 6'6" tall and I weigh 380 lbs, but I carry it well, so I can attest to that statement) or a dry sponge sucking up water, or maybe even a Bounty paper towel doing the same thing like their TV commercials advertise.

    Organic tissue loves microwave energy, and will wick it away, pull it directly, whenever and wherever possible, even if it's just within close proximity - and guess what? The level of the absorption rises if you make direct skin-to-antenna contact, ofttimes geometrically. I'm not trying to scare people into thinking "OMG my cell phone is a microwave oven next to my brain and it's frying me up like fried chicken!!!"

    No, it's not, because the levels of energy being transmitted by any cellular phone on the market today are so low that they simply don't have the effect that sticking your head inside an actual microwave oven and turning it on would. Proximity, transmission power, absorption rates, etc, it all plays into it. You're safe, using the iPhone 4 or any other cell phone, at least in terms of the levels of radiation (meaning the microwave energy radiating off the antenna(s) in cell phones) overall.

    Wanna know the simple explanation? Organic tissue doesn't pass microwave energy with any appreciable level of efficiency - it absorbs it, a vast percentage of it. It doesn't just pass through our bodies/hands/fingers 100% untouched (no pun intended), a significant portion of the energy is absorbed by the organic material and at that point that energy is "lost" forever.

    And Apple is quick to announce, as most cell phone makers do, that holding a cell phone can alter the signal reception as well as signal transmission. Why? Because your hand wrapped around the phone - in any position you choose - is going to wick microwave energy away and that's called attenuation. There's also an issue of antenna detuning but I'm not talking about that aspect right now, that's later.

    Attenuation is simply the loss of some signal energy, whether it's being received by the phone or it's being transmitted, because of either a) blockage by some object outright or b) absorption of energy by some object. You're either blocking a percentage of it and almost nothing is getting through, or you're absorbing a percentage of it. It works out the same either way as signal is lost, hence performance suffers, hence you either lose data or the connection is severed.

    It's perfectly normal for a cell phone to respond to attenuation when held by the signal strength display - commonly referred to as "bars" - on pretty much every cell phone that exists today. Why? Because today's cell phones are all digital - they're sending very low power data streams to the cell sites/towers that cover a great percentage of the planet's populated surface - not as much as AT&T and Verizon claim, however. :D

    Cell phones that operate with such incredibly low power transmissions are by design going to have to respond to the signal attenuation caused by holding the phone in the hand, by holding the phone in the hand while inside a car, while holding the phone in the hand while in car inside a parking garage, and so on and so on. The phone's work in conjunction with the cell sites/towers and adjust themselves accordingly either by increasing output power or hopping frequencies as required - this is perfectly normal operation, and the iPhone 4 and all other cell phones do this, 24/7 when they're in operation, even when you're not on a call.

    NOTE: I'm talking about the phones, not the cell sites/towers which stay pretty much constant for power output, they have no reason to alter much of anything since they are stationary. Cell phones adjust themselves to the conditions by altering power and frequency to maintain what their internal programming deems to be the best and most reliable signal - that doesn't mean the strongest because that is actually a problem too but it's not something I'm going to get into this time out.

    The iPhone 4 is not unique - it works like every other cell phone that exists today does. Holding it in the hand causes signal attenuation, that's a fact and cannot be disputed because it's a cell phone and every cell phone (not just every iPhone 4) does this, be it a phone made by Nokia, Motorola, LG, Sony/Ericsson, Samsung, HTC, I don't care. Apple was quick to "cover their ass" after Steve Jobs made that fateful comment to samcraig (a member here at MacRumors) and told him "Just avoid holding it in that way" as an actual solution.

    Apple quickly followed up with the standard disclaimer that I've basically just covered: that all cell phones will exhibit some signal loss/degradation/attenuation when held in the hand, it's a fact of life, deal with it.

    Ok, fine, we got it.

    But not many other phones that I've ever owned suffer such signal attenuation to the degree that my iPhone 4 has, from 5 bars to 1, within a few hundred feet of a cell site/tower with absolutely nothing blocking/obstructing the signal path from my iPhone 4 to the antenna on the site/tower except my hand. And it gets worse, but for that you'll need to look at the post(s) linked in my sig, I'm not going to repeat my first-hand or should I say first-fingertip experience of killing my iPhone 4's 3G connection with a fingertip.

    So, if Apple is rumored to be releasing some unofficial "fix," what's the big deal, you ask? Well, it's that bumper thing. Ever since I first saw it demonstrated/shown at WWDC during the iPhone 4 introduction - and knowing that the iPhone 4 has a metal band that's actually part of the chassis - it's really bothered me for many reasons I didn't have anything to base the gut feeling on till I actually got my iPhone 4 in my hand, and when I then noticed just how bad the degradation is, as well as my Dim Mak-certified fingertip-of-death touch on the lower left side, well... it all become clear.

    Occam's razor says the simplest explanation tends to be the right one, so here's my explanation:

    "The iPhone 4 is a device that works as a cellular phone working on frequencies in the microwave range, both in reception mode and transmission mode (which is simultaneous given the nature of cellular communications). Because the chassis is part of the makeup of the iPhone 4, and because two significant portions of the chassis are designed to act as resonators, aka antennas, the close proximity of a human hand - in the situation where some type of bumper or casing is applied to the iPhone 4 itself - as well as direct skin-on-metal contact is going to occur - in the situation where no such bumper or casing is applied or in place - detrimental effects are going to be taking place because of the properties of microwave energy reception and transmission."

    Want it even more simplistic? Sure thing...

    "The iPhone 4's antenna design is fundamentally flawed because of the potential for skin-on-metal contact which would dramatically attenuate signal reception and transmission to levels that cannot be adequately resolved by altering the power transmission or even the channel/frequency assignments."

    The Occam's razor/br0adband's firsthand experience of owning an iPhone 4 suffering from said issues version?

    "The bumper is Apple's solution to preventing skin-on-metal contact in the hopes that it'll fix the fundamental design flaw of making the antennas part of the chassis of the iPhone 4."

    Think about it.

    - You've got a phone, with a metallic band that's designed as the antenna.
    - You've got the basic principles of microwave energy transmission that say organic tissue + direct contact with a microwave resonator = very bad thing for organic tissue and even worse for the device considering the already low power nature (meaning the skin's going to wick away so much energy the phone isn't going to be able to accommodate it and handle the necessary output to overcome that loss).
    - You've got to come up with a solution that addresses the skin-on-metal contact potential and come up with it quick because this problem appeared way too late in the production phase to change things now
    - You've got some smart people working for you and their solution is bumper that serves first and foremost to solve the inherent design flaw: it prevents skin on metal contact, completely
    - Problem solved

    Not quite. Because people with bumpers are still having the issues, which is accounted for by saying (again) that the iPhone 4 is not unique in it's signal attenuation issues when held in the hand, but it is unique in the degrees to which the signal is being attenuated and sometimes losing the signal and service completely.

    If Occam's razor is applied to the issues the iPhone 4 is having and will continue to have because of the metal band being the antenna, the simplest explanation and solution is the bumper. At least that's what Apple was shooting for... unfortunately, as many iPhone 4 owners with bumpers are discovering, even that isn't helping.

    Told ya it was a long post. ;)

    While my firsthand experience is somewhat extreme (killing mine with a fingertip takes less than a minute, even standing under a cell site), the majority of people that ARE reporting problems are all doing so with claims that are very similar to mine. If I were the only person on earth with an iPhone 4 and I was the only person that had these issues, and posted about it, then someone would be more than welcome to say "Your phone - your specific iPhone 4 - is probably defective and you should have it replaced." and I would fully agree with that solution.

    But I'm not the only one, not by thousands.

    This is a real issue, and it's affecting real people, not just me myself and I. I know a lot of people will dismiss this whole post and rant about it, that's fine, I can't control stupidity and ignorance, nobody can except each individual for their own stupidity and ignorance.

    I think about Occam's razor, apply that to the iPhone 4 and what the metal band as antenna is causing - not for every single owner, I agree, but not every single owner is going to complain: thousands upon thousands of iPhone 4's have been returned or reported with Apple Support and not on Internet forums, and what's worse is that people returning iPhone 4's for replacements are now finding the replacements suffering from the same issues.

    Clue me this: if I had a knock at my door, and it was Steve Jobs, and he said "Let me see your iPhone 4" and I handed it to him, then we walked the 25 feet to the balcony of my apartment building and I showed him how I'd held it in my testing, and he did exactly the same thing, and he put his official Apple certified fingertip on that seam and the phone lost signal and service inside of 60 seconds, what do you think he would say?


    I've done my best to make sure this is accurate based on my decades of working with radio communications equipment - if I made some typos, grammatical errors, I apologize, but I'm done with it as I'm posting it now. I won't make edits... if I have anything to add I'll do it in the thread with additional posts.

    And if you read this whole damned thing, even if you disagree with every single point I've attempted to and hopefully have made, I salute you.
  2. Romanesq macrumors 6502a


    Jun 16, 2003
    Darn good post

    And dead accurate.

    I know. I have the finger of death too.
    Electrical tape layered several times didn't work either.

    It's trouble when a friend tells you "You've had alot of dropped calls recently" and doesn't even know you have an iPhone 4.


    Have a polyurethane plastic case and it is not enough to stop the finger of death. New hard (plastic) cases coming via Ebay. Those kept the 3GS pristine. :cool::cool:
  3. gtmac macrumors 6502a

    Jun 25, 2010
    Don't forget the insane margins on the bumper vs. the iPhone. Apple is making a killing on bumpers. Even at the low price given the margins that 10% additional revenue becomes quite a bit of income.
  4. br0adband thread starter macrumors 6502a


    Aug 29, 2006
    I worked out that the bumper is probably around $.20 USD to make (that's twenty cents) based on some data I found by a friend who did a marketing report on some Asian tech firms that make such products (quite a few, actually). Considering that, if true and it's somewhere in that range (maybe a quarter, twenty five cents USD, max) at the $29 price Apple is looking at 14,400% profit on each bumper sold...

    Or close to it.

    In that same post I'd made I mentioned that if this is a coating issue, that's one of the big theories/rumors still floating around (some coating on the metallic band that works as a dielectric to prevent skin-on-metal directly), and a ton of iPhone 4's either have a defective coating or they didn't get coated at all (this is all speculation, folks) that when given the choice between a coating - which could cost Apple a few pennies per phone - versus selling consumers a $.20 USD rubber band that provides effectively the same solution and makes them an obscene amount of profit, anyone with any business sense at all would say "Bumper ftw!!!"

    Occam's razor applies there too, it seems. Coating for additional cost, no profit, or bumper for mo' money mo' money mo' money... simplest solution coupled with that insane profit = bumper.
  5. randomerratum macrumors 6502

    Dec 3, 2009
    Santa Monica, CA
    Wirelessly posted (Mozilla/5.0 (iPhone; U; CPU iPhone OS 4_0 like Mac OS X; en-us) AppleWebKit/532.9 (KHTML, like Gecko) Version/4.0.5 Mobile/8A293 Safari/6531.22.7)

    I don't know. I just don't buy it.
    I don't buy that they didn't test for this, as a current death-gripper myself I just can't see how they could actually miss this one. It's GOT to be a software/calibration issue. I cant hold my phone naturally in my left hand (while looking at it) without seeing 3 bars fall away. I havent dropped any calls from it, but having no bars sort of jumps out at you in this modern cellular world. I mean MAYBE they forsaw it being a problem for *some* people and created bumpers, but I can't imagine it's worth all the bad press they're getting. Most users won't get an apple bumper but a 3rd party case anyway.

    I just don't buy it. They may be arrogant, cocky and ballsy, but Apple just isn't stupid.
  6. Iyktyn macrumors newbie

    Jun 17, 2010
    Its a good look at the issue, and I do like the observation, but I have one question. If it is indeed all about blocking the signal by organic matter, why is that I can block more or less the entire parts of each antenna by themselves or together even, but yet the only time I see a drop in signal is when the barrier on the lower left corner is bridged. Again I just want to say I understand how the signal and radiation as a whole is absorbed(my background is in molecular and micro biology) but it just seems strange that it is only when bridged does the signal drop and for me completely(Also I always test through looking at down and up load speeds instead of just the bars since they can lie). This would lead me to believe that it would be interference between the antennas causing the problem and not the absorption by the body itself.
  7. br0adband thread starter macrumors 6502a


    Aug 29, 2006
    There's a simple theory that the further you go in opposite directions, the more alike the ends become, or something like that. The most common example is of heat and cold: when you approach the extremes for each, extreme heat and extreme cold, they both take on properties of the other. Being exposed to extreme cold "burns" the skin, destroys it in basically the same fashion that extreme heat can/does.

    There's also a simple statement that I've used in sigs for years now:

    "The difference between genius and stupidity? Genius has limits..." so...

    I've been working with computers for decades, and while the majority of the people that I've worked with and continue to work with consider me a "God" when it comes to this stuff, even I make rookie error sometimes.

    Again, Occam's razor comes into play here:

    Apple professes pure genius in everything they do, nothing is ever second best, nothing is ever left to chance, etc. Is it so absolutely unbelievable to think that with the iPhone 4 that they made a classic rookie error in this situation, screwed the pooch too late in the game to be able to recover the fumble?

    The simplest explanation - the bumper - is pretty spot on for a solution, at least from the engineering aspect. I made note (forgot to mention it in the megapost above) that where I called the bumper a practical solution I clarified what I meant by "practical:"

    The bumper is a practical solution meaning it's elegant, simple, efficient, and in the same exact situation - with no other potential solutions - I would most likely have said "Yep, that'll cover it... pun intended" because it solves the most trouble-making aspect of the metal antenna band itself which is we can touch it.

    I asked someone to show me evidence or proof of any device using radio waves where touching the antenna is actually part of the design and one person, only one person tried to accommodate my request. He posted some kind of Sony FM radio or whatever that uses a lanyard style antenna that not only holds the device but loops around the neck and becomes the antenna.

    That's fine, but the antenna is coated in rubber, the dielectric which prevents skin-on-metal contact, and so his answer - while creative - simply didn't fit the given situation nor the example.

    Oh well...
  8. Apple-NoEscape macrumors 6502

    Mar 25, 2010
    United Kingdom
    I don't see why you write all that for something that alot of people have been saying. Even myself, I have posted in a couple threads suing how the bumper was only created due to apple realizing their mistake too late.
    However I don't believe it's our body absorbing it that's the problem, it's the fact we are bridging the two seperate anntenas.
    If it was the fact we were absorbing the radio waves that was causing the problem then we would see it happening anywhere We touch on the phone. (btw I am not arguing that we don't absorb the waves, as I know we do we are basically being microwaved 24/7 nowadays, just that that isn't the main issue here)
  9. cbruce76 macrumors member

    Feb 5, 2008
    A bit verbose and repetitive, but it appears to be a plausible theory.
  10. SiskoKid macrumors 6502

    Jul 12, 2008
  11. chris.robison macrumors regular

    Feb 16, 2009
    Sounds good seems right.....BUT....

    - Out of 1.7 million phones sold, not all seem to have the issue. A lot yes, but definitely not all. I am waiting to buy mine, but went to the Apple Store in SLC, UT and the demo phones did not have the issue.

    - I have not read a single report of reception issues of iPhones with bumpers.
  12. TuffLuffJimmy macrumors G3


    Apr 6, 2007
    Portland, OR

    Anyone want to summarize for the lazy members?
  13. 41qser macrumors regular

    Sep 5, 2007
    1. No new point was made.

    2. In the spirit of Occam's Razor, K.I.S.S. Textual diarrhea impresses no one but yourself...
  14. br0adband thread starter macrumors 6502a


    Aug 29, 2006
    Well, I'd say that leans over into the theory of the detuning issue. Attenuation by absorption or contact doesn't mean the same thing as detuning. Think of it this way:

    If you had a flashlight and you shined it on a bare wall, you've got "full signal strength" you could say. Now, place half your hand over the lens of the flashlight and block half of it, so hopefully the spot on the wall now becomes a half-circle, or half-moon, etc.

    That's attenuation - you're altering the signal strength and only that.

    Now, since light is made up of many frequencies - it's energy, you know - operating on different wavelengths just as a cell phone does because it's designed to alter frequencies as required (it can retune itself), the way to detune a beam of light would be to throw a filter on it.

    Take a red lens and put it on the flashlight, shine that on the wall, and you just detuned the full spectrum down to the one frequency of light. Change that to green and you retuned it to another frequency.

    While attenuation is what's demonstrated by the signal bars on cell phones when it's 1 bar, 3, bars, 4, 5, whatever, detuning isn't something that can be as easily demonstrated or signified with an icon.

    When the iPhone 4 - and any cell phone - detunes and starts to hop frequencies (and there are hundreds of them, if not thousands, inside the specific frequency ranges that they operate on), it retains the signal with the cell site/tower but it's just changing the frequency of operation. Cell phones operate with two channels: a control channel as well as the actual channel where data comes/goes from the phone.

    The control channel is always active because it comes from the cell sites/towers - it's never not there, basically. It's the channel that tells all the cell phones in the area "Hey, I'm here, if you want to contact me, here's a frequency that's open, identify yourself and let's make a connection."

    The control channel doesn't actively jump all over the place - and for this example, channel = frequency. The communication on the control channel is one direction only - from cell site/tower to the phone. It's like a beacon in some respects, only sending info and never getting anything back. The control channel is what all cell phones associated with a given cell site/tower use to get their association, their notices, etc. It all comes from the control channel.

    If customer XYZ has a cell phone and it's associated, the cell site/tower is telling that phone "Ok, you're recognized, use channel 123 which is currently unallocated" and the phone switches to doing two-way communications on that channel (which is also a frequency, by the way). The most important principle here you and everyone needs to understand is this:

    Loss of service occurs when the control channel data is non-existant or when enough of the control channel data/signal can't reach the phone so it can "lock on" and then switch to a channel that the cell site/tower is saying is open and available.

    You can lose signal, lose a lot of it, but you're still associated with the cell site/tower because you're receiving the control channel - as long as that works, you're still considered as "having service" by the phone and the service provider.

    You can lose pretty much ALL the signal on the channel that you're associated on - meaning you drop a call, your data stream gets disrupted, you get static, noise, audio streaming sites disconnect or buffer more frequently, etc, all sorts of nasty things - but you're still receiving the control channel data and hence, you're still "having service" even in spite of you not being able to do a damned thing.

    Again, for clarification - cell sites/towers provide two functions:

    1) They constantly broadcast a signal known as the control channel, on a frequency that does not alter, with a solid level of power that doesn't fluctuate at all. The control channel is picked up by cell phones that want to associate with it, they are told by the control channel which channels are open for communication.

    2) They provide the channels which are used for communication and assigned by the control channel.

    Say you're in the middle of a big office, with a central dispatcher in the middle of the room, sitting at a desk that's visible no matter where you are in the room. The dispatcher calls your name and yells out "Joe, pick up line 123" and so you do. The dispatcher only dispatches calls, he does not talk to you at all, he only directs you to which line you're supposed to use to communicate with the rest of the world - even if you yelled at the dispatcher he'd just ignore you because he can't hear you. He's the beacon...

    Say you pick up line 123 and start having a conversation with Mike over in some other location, and as you're speaking to him, the connection turns crappy: static, noise, and finally it just disconnects completely.

    At that point you can still see the dispatcher, you can still get his communications when he yells them to you, but you've lost Mike totally. Sure enough, a few seconds later the dispatcher yells out "Joe, pick up like 169" and you do, and it's Mike who promptly says "No idea what happened there, lost you for a few moments."

    And there you have the most basic way I can describe cellular communications. The dispatcher - the control channel - is being broadcast by cell sites/towers 24/7, it never ends, it rarely ever fluctuates in power, and it's always sending new instructions to the cell phones within range on how best to connect with the communications channels that it provides.

    How does this all relate to the iPhone 4? Attenuation can cause you do lose the signal from the dispatcher as well as any channels you're actively using: dropping a call equates to losing a channel while still being associated with the control channel/dispatcher - losing service means you can't even hear the dispatcher anymore and you're dead in the water.

    Attenuation happens because of hands, bodies, cars, buildings, brick walls, skyscrapers, etc - not much can be done about it except jack up the transmit power of the phone to keep the communication channels open (not receiving, that only affects transmitting from the phone) or retuning to a different frequency in the hopes of maintaining the connection.

    The worst case scenario: attenuation so bad that not only does it end up with complete loss of service (can't hear the dispatcher) but you can't hear control channels (dispatchers) on the other cell sites/towers in your area. That's as bad as it gets, and is quite frequent with the iPhone 4 because it seems to lose signals because of the increased attenuation because of the metal antenna that's part of the chassis.

    Do other cell phones exhibit this behavior? Yes, to some degree Do other cell phones seem to exhibit this behavior as dramatically as the iPhone 4? No. Why? The metal antenna band, simple.

    The detuning issue is most likely the software fix that's been rumored - you can reprogram the iPhone 4 with a better algorithm for switching channels to maintain calls/data connections, I fully believe that to be a possibility without issues.

    It's entirely possible that in testing they simply didn't do enough widespread testing and instead focused on some area where signal levels were so predominantly high that this low signal issue which gets worse because of the metal antenna band and skin-on-metal contact can handle didn't crop up until it was too late to do anything about it before the iPhone 4 hit store shelves.

    Is it fixable? I believe the attenuation/detuning issue is, and probably will be.

    But then there's the issue of the bridge disconnect by creating a connection between the two antennas... that's the hardware issue, and I don't think it can be resolved by the firmware because even when the Wi-Fi/GPS/Bluetooth antenna isn't in use and those services are completely disabled, I and many other people still have signal loss and loss of service, so it's not as simple as a "Just turn off those services" answer from Steve Jobs if he's even considering one.

    Cell phones are always listening to the control channel of the cell site/tower (the dispatcher) that they're associated with. As long as that reception - since cell phones only receive that data, 24/7 - is there, you'll "have service" even if you can't make a call at all (by using channels assigned by the control channel/dispatcher) because you can't get a decent connection on the communication channels (where you receive and transmit, aka make calls or do data transfers).

    Sounds complicated, and in many respects it is, but... that's about as plain as I can make it.
  15. br0adband thread starter macrumors 6502a


    Aug 29, 2006
  16. Slip Jigs macrumors 6502a

    Feb 18, 2008
    Did you really need all those words to say what you had to say?

    I doubt it.

    Probably could have said it in a single paragraph.

    I didn't read it.
  17. bli625 macrumors 6502a


    Mar 8, 2009
    Wirelessly posted (Mozilla/5.0 (iPhone; U; CPU iPhone OS 4_0 like Mac OS X; en-us) AppleWebKit/532.9 (KHTML, like Gecko) Version/4.0.5 Mobile/8A293 Safari/6531.22.7)

    Dude, awesome post! Very in-depth and analytical. I will finish the second half in the morning.
  18. bli625 macrumors 6502a


    Mar 8, 2009
    Wirelessly posted (Mozilla/5.0 (iPhone; U; CPU iPhone OS 4_0 like Mac OS X; en-us) AppleWebKit/532.9 (KHTML, like Gecko) Version/4.0.5 Mobile/8A293 Safari/6531.22.7)

    Yeah... The iPhone 4 has reception issues. :p
  19. br0adband thread starter macrumors 6502a


    Aug 29, 2006
    Perhaps, but then you wouldn't learn anything. Oh, wait, you didn't.

    But you just did.
  20. wingnut8 macrumors 65816


    Jun 8, 2007
    iPhone 4 has reception issues, and they found out too late to fix it.
  21. KBlessitt macrumors newbie


    Jun 23, 2010
    I completely understand that the Bumpers are over priced but...... You figured up the price of the bumper to be say .20-.25 cents. You may be correct in that there is .20 cent worth of material in the Bumper. Apple or (the company that actually makes it) paid more for the material used in the product. For every buyer that sales it or the material there is more markup from the next seller. the actual base price for the materials not including the labor involved in the producing it might possibly be .20 cents but by the time it makes it to store shelves there is - the material, labor for (design, build, packaging) the delivery, and for the stock boy at the apple store or the tech guy that keeps the digital stock computer going. There is a lot more that goes into the bumper that the .20 cent material. I do think they are overpriced and should be around 10 - 15 dollars.

    So .20 cents is for the person who actually makes the plastic, rubber and all the labor, delivery, packaging, stocking adds to the price.

    You cannot base the price on a product for selling only on how much it cost to produce. Apple is still a company and the reason for a company is to make profit albeit they could do the same if they had a lower price.

    Just my professional opinion.
  22. Slip Jigs macrumors 6502a

    Feb 18, 2008
    No, I didn't. Not anything new, that's for sure. But if you're concern is to teach, then you should work on presentation.

    You commented on someone's one word reply. Well, the forum is no place for such dissertations either. Really tho, if you like writing that much and feel you have something new to add to the discussion, then start a blog. Plenty of free solutions out there.
  23. chris.robison macrumors regular

    Feb 16, 2009
    Umm.... that video is cropped and doesn't show the whole phone. For all I know, he has the bumper lifted at the bottom...

    A quick search on YouTube only yielded bumper success stories.

    Many yes, but relative to the amount sold? I don't doubt you are having issues, but still...

    So what are you going to do? 30 day return policy...
  24. MrSingh macrumors regular

    Jan 2, 2010
    Apple would be giving out these very, very cheap to produce yet effective bumpers 'out the box' for free if they truly wanted to squash the issue and avoid as much negative press and consumer-reaction.

    to not only sell them as a peripheral, but then to price them so high so there isn't 100% take-up, doesn't make sense...they're greedy but surely not that greedy???

    therefore i think a software fix is imminent; how effective it will be remains to be seen...
  25. br0adband thread starter macrumors 6502a


    Aug 29, 2006
    If you, like some others probably will, wish to slam me for technical accuracy, that's one thing and I'm willing to work with it, but if you're slamming me just because I decided to post some information and a potential theory for what's happening and information that might be helpful to someone - if even just one single person - then you can take it up with a Moderator after I report your post.

    It's MacRumors, a website and forum about Mac, Apple, the products, the people, the community, etc. My posts (aside from the jab at you which you deserved, I think) should be taken as such.

    Don't like it? No reason for you to even bother stopping by this thread, is there?


    I'll keep it till Apple does something and then it'll be returned. The person that purchased it for me is aware of the issues, and bought it on his AmEx Gold card (he's been a member for 37 years) so, he sure as hell ain't paying for it in this condition, and I've already stated that I'll keep it till Apple does something or announces something and then I'll be sending it back.

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