iPhone 4 - signal propagation issues because of "the band"?

Bahamut

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While I do know something about radio wave propagation (been a licensed HAM for 30+ years now) I gotta say this is downright interesting:

http://www.youtube.com/watch?v=-ixIHyEPO5g

I do know that with some cell phones you can actually get such widely fluctuating signal reception/transmission with just a slight movement of the phone - reminds me of days long past with Motorola "brick" phones and people twisting their heads in funny ways to maintain a signal - but this is truly insane at the sheer level of signal strength and just how fast it happens. My belief when I heard about this new design was that it could potentially work better by using the contact with our bodies as a potential pathway for better signal reception/transmission - but alarmingly, and based on this video's "proof," perhaps that band is not quite what Apple would hope it is.

I suppose we'll get a lot more information about this potential "issue" soon, but... when your hand becomes "the dead spot" that's pretty severe I'd say.

Anyone else able to duplicate this guy's test for themselves with their own iPhone 4 if you've already got one and it's functional? Would love to see/hear other people's opinions...

And of course, Gizmodo is all over it too with several other videos by the same poster and other folks too:

http://gizmodo.com/5571171/iphone-4-loses-reception-when-you-hold-it-by-the-antenna-band?skyline=tru
 
It's definitely a real problem. If I hold my phone with my bare hands, a reception bar ticks away every two seconds until I'm at 1 bar or "searching." If I wrap the edges of the phone with my shirt and hold it, I do not lose any reception bars. I've tested this multiple times. I don't really care though. I'll be getting a case for it soon and it won't be a problem for me.
 
If you cross connect the antennae via your hand, you will lose signal quality. Simple.

But retarded. I hope the fix it by the time I get my toy iPhone...
 
Yah, was reading through the MacRumors thread about this (where the story started) and people using cases of any kind say it's not really an issue for them, but if you're holding it in your bare hand... seems that "capacitive touch" is killing it, oddly enough, turning the skin itself into a sink that's just wicking off the signal strength fairly severely.

Damn... this does not bode well for the moment.
 
On the bright side, for me anyway, I can sleep in tomorrow instead of getting in line.

This issue is way too serious for me to ignore. How was this not noticed during testing? Maybe it's just a sinister plot by Apple to sell us all colored rubber bands (they call 'em bumpers) for $30
 
I just realized if this turns out to be for real (so far it sure as hell seems to be) it could be a sure-fire reason for why Jobs was having such problems with the iPhone 4 demo at WWDC... when I watched that I couldn't help suspect "the band" idea might have something to do with it given how signals propagate off the device but, I dismissed it at the time thinking they'd have thought of this in development and testing.

Now I have to wonder. I always believed the reason for the glass back on the device was to use an antenna - a larger one - under the glass where it could pass through without issues like you have with a metal backing plate, but apparently this might turn out to be a bad thing in the long run.

Not good... not good at all. But it would definitely explain those issues at WWDC in spite of there being over 500 unique APs/SSIDs in operation as well.

And I am starting to see a lot of speculation (just as the poster above said) that there could be something to this and Apple's "bumper" idea... we just have to wonder I suppose. I'm personally of the mind that if you're getting such a device you'd best be protecting it with SOMETHING, now I have to wonder if this is all a forced concept to sell cases (?!?!?!). Hrmmm...
 
And I am starting to see a lot of speculation (just as the poster above said) that there could be something to this and Apple's "bumper" idea... we just have to wonder I suppose. I'm personally of the mind that if you're getting such a device you'd best be protecting it with SOMETHING, now I have to wonder if this is all a forced concept to sell cases (?!?!?!). Hrmmm...

I think the Bumper is meant to guard against such reception problems. I think the issue is physical human contact, not contact with non-conductive materials (plastic cases).
 
Seems that some folks sending in videos to Gizmodo (and they're getting more by the second) have noted that as long as you're not touching the bottom band it doesn't seem to drain/kill off the signal anywhere nearly as bad as just the left and right sides. At first I was noticing everyone holding it the same way and they were always putting a thumb or finger on the volume buttons; I suspected a potential grounding issue there but, some other videos have surfaced where people don't touch those at all so that's a wash.

This article by a Danish antenna expert (on cell phones, no less) makes valid points that were something I'd considered myself based on the human/antenna capacitance happening when that contact is created (it's in Danish so this link is the Google Translation, not perfect but you can understand what he's saying for the most part):

http://translate.google.dk/translat...d-antenne-problemer-1.362104.html&sl=da&tl=en

And as noted, this is the first time Apple itself is doing a first-party case of their own, so people are obviously now starting to wonder if there really is something going on because of this now fairly confirmed issue. Honestly, right now I'm leaning towards a "yes" on that aspect. :(

Edit:
This video clearly demonstrates the "touching the bottom" point:

http://www.youtube.com/watch?v=4gb3aQ5XoQw

That one is point-of-fact right in your face the one...
 
From Walt Mossberg's iPhone 4 review:

Both Apple (AAPL) and AT&T (T) told me they worked to make the iPhone 4 do a better job with AT&T’s network. For example, the phone itself is surrounded by a prominent stainless-steel trim piece that acts as a large antenna. And Apple said it also tuned the phone to try to grab whatever band on the network was less congested or less affected by interference—to stress the quality of a signal over its raw strength. AT&T said it, too, made some changes to its network with the new iPhone in mind.

But, in my tests, network reception was a mixed bag. Compared with the previous model, the new iPhone dropped marginally fewer calls made in my car, both in Washington and in Boston, and was much louder and clearer over my car’s built-in Bluetooth speaker-phone system.

Yet, in some places where the signal was relatively weak, the iPhone 4 showed no bars, or fewer bars than its predecessor. Apple says that this is a bug it plans to fix, and that it has to do with the way the bars are presented, not the actual ability to make a call. And, in fact, in nearly all of these cases, the iPhone 4 was able to place calls despite the lack of bars.

It's not a signal issue, it's a signal reporting issue which is known and will be fixed. Noteworthy but ultimately not a big deal, IMO.
 
From Walt Mossberg's iPhone 4 review:



It's not a signal issue, it's a signal reporting issue which is known and will be fixed. Noteworthy but ultimately not a big deal, IMO.

that would be believable if there weren't reports of entire loss of network connectivity and non response on voice calls.

Heres an idea... Full cover invisible shield, put the edges on only. Non conductive buffer ;)

Cause I certainly don't want bumpers on mine.
 
I've been using my iPhone 4 all day, not a single problem or dropped call. In fact, reception has been better vs. my 3GS, 3G, and 2G.
 
Heres an idea... Full cover invisible shield, put the edges on only. Non conductive buffer ;)

Cause I certainly don't want bumpers on mine.

This is exactly what I was thinking. I don't want the bumpers either. If I get a case, it certainly wont be from Apple. The design of the bumper is piss-poor if you ask me. The sides of my phone never get scratched, only the front and back.
 
Do you have a bumper on yours or is it naked?

Mine is fine as well and it has no bumper or case.

Ive noticed it drop like one or two bars when I touch it but it goes right back up(While I am still holding it) and it doesn't do it most of the time. I have not had a dropped call or failed text yet either.
 
I've been using my iPhone 4 all day, not a single problem or dropped call. In fact, reception has been better vs. my 3GS, 3G, and 2G.

If you can, or would you try that "thumb" test as shown in that last video linked above? Place the phone on a flat surface, check the signal strength/reception (the bars), then touch it - without actually picking it up or moving it, if possible - so you "short" the two bands on the lower left side and hold it there for a few moments and see if it affects the level of the bars?

Would love to know the results. Some folks in extremely high signal strength areas are saying they don't note such issues - but at least they're honest enough to make that disclaimer to begin with. Not everyone lives within a quarter mile line-of-sight of a cell site but, some folks do and they're not having the problems. It's obvious that anything - walls, trees, buildings, etc - that blocks the signal off the cell site can do harm to the signal strength but this seems to be tied more directly to the design of the antenna(s), in other words it does certainly appear to be a design issue.

Not absolutely confirmed but, again, it's popping up with such a frequency on multiple sites with people that did get their iPhones today that it's quickly becoming a real issue.
 
I've been keeping track of this throughout the day. What I realized, though, is that I hold my phone in a "claw"-like fashion. I have one thumb on the left side of the phone, about 3/4 of the way down, my index on the back, near the Apple logo, and three on the right side, my pinky on the lower corner and my middle about half-way up the side. I don't "cup" the phone with my palm or anything: it's all just finger tip contact. It doesn't seem as if this will be an issue for me unless I let my pinky get a little rogue and brace the bottom of the phone with it. Judging from the videos, it's the "cupped" grip that has the potential to cause signal issues.
 
One brilliant thing I just caught over at MacRumors:

Because of the highly sensitive aka fucking paranoid behavior of Apple with respect to the secrecy around this product pre-announcement/pre-release, the majority of the testing by people in the field most likely - note this is probably true - was done with the iPhones in cases to protect them/keep prying eyes from noticing what they were, perhaps even the "bumper" cases or something similar and if that's actually the case (pun not intended but hey, it's funny how that works out) this issue of the potential bridging the two seams and causing a signal issue would have been basically overlooked completely.

Man, this is just snowballing now...

Just saw this also, too funny:

originalzm.jpg
 
One brilliant thing I just caught over at MacRumors:

Because of the highly sensitive aka fucking paranoid behavior of Apple with respect to the secrecy around this product pre-announcement/pre-release, the majority of the testing by people in the field most likely - note this is probably true - was done with the iPhones in cases to protect them/keep prying eyes from noticing what they were, perhaps even the "bumper" cases or something similar and if that's actually the case (pun not intended but hey, it's funny how that works out) this issue of the potential bridging the two seams and causing a signal issue would have been basically overlooked completely.

That... Is hilarious, but also shitty beyond belief for us. I mean, I can understand Apple wanting to be secretive about its products, but I think they shot themselves in their foot this time.

Like I said before, I personally don't care that much, I'm going to put mine in a case, so it's not that big of a deal to me. But, this is a HUGE produce design flaw none the less, and will be forever a stain on Apple if the reports are true.
 
I read that comment about the cases during testing and realized "Hey, when that guy found the iPhone 4 in the bar in SoCal, the first thing they pointed out was it was hidden inside a fake iPhone 3GS casing..." and then I laughed pretty hard before making that post above.

Wouldn't that be something to find out this is a for-real design issue (looks that way by all accounts over the past few hours) and the whole "hide it inside something" concept backfired by hampering the actual "innovative" design that exists now?

I mean... really, anybody with any common sense and basic understanding of antennas and wave propagation would almost instantly say "Don't touch the antenna, you're gonna mess things up if you do" and here Apple designed it with antennas that function as the case itself?

I tell ya, it's just getting worse by the minute.
 
I think the invisishield fix would work. I posted that as well over in the official Apple forums. Its a design flaw for sure, and its super shitty that you would have to fix a new phone, but with the film it should be a 1 time fix. You could put the film on the back, then cut two strips out of the front film and apply it to the band on either side.

Apple needs to put a clear coat on this steel band, bam problem solved.

P.S. ITS NOT SOFTWARE RELATED. Videos show Data speeds either dropping drastically to disappearing all together.
 
It works fine if you hold the phone by 2-3 fingers. Thumb on one side. Two on the other. I'm getting 2-3 bars consistently where I never got service before. I'll deal with holding it like this until I get a bumper case. (posting from it now).
 
Another video showing it most definitely has something to do with direct skin contact on the chassis/antenna bands:

http://www.youtube.com/watch?v=Y1KFgiwm-Q0

I really gotta wonder how the hell this slipped by, but then again I am also firmly committed to suspecting this was discovered somewhat late in the development (perhaps when someone actually took off those silly fake housings) and discovered "Oh crap, what are we going to do now, we can't just scrap this and start over..." and wham...

Someone decides to make a bump case. Note the concept of "bump case" came from Tablet PCs years past, silly trivia but entirely true.

As I noted in a post at MacRumors, this situation with direct skin contact on the metal itself and Apple bringing out a case specifically for the iPhone 4 at exactly the same time is just too much evidence for me of something wrong and their attempt to continue the development and release of the product while hoping that nobody would notice.

Fat chance of that, this cat's outta the bag now.

Someone made a comment about the bump case costing 60 cents to manufacture and being sold for $29 is pretty funny but, who's laughing now?

"Defective by design" is all that keeps coming to mind this morning. Man oh man...
 
Its not bad at all, it barely effects mine and I never lose all bars.

I am not buying a bumper.
 
This article by a Danish antenna expert (on cell phones, no less) makes valid points that were something I'd considered myself based on the human/antenna capacitance happening when that contact is created (it's in Danish so this link is the Google Translation, not perfect but you can understand what he's saying for the most part):

http://translate.google.dk/translat...d-antenne-problemer-1.362104.html&sl=da&tl=en
I think what he might be getting at is not that the touch is 'grounding' the signal, but that it's de-tuning the antenna enough that the RF system is becoming very inefficient. High frequency signals like modern cell networks require very close impedance matching or there's a lot of loss, so even a slight change in antenna impedance could cause fairly significant problems. I'm not an RF engineer, but I also wonder if the extra reflected power (the cause of the loss is that power launched into the antenna reflects back and forth in the transmission line rather than being radiated; the amp must absorb those reflections, so will heat up more) might be forcing the transmit amplifier to reduce its transmitted power so as not to burn itself up.

If this turns out to be the real issue it appears to be, I really can't believe it got through Apple's QC. Or even past their engineering department. It's such a fatal flaw I have no idea how it could have even made it to prototyping.

I'm curious what they'll do about it if it turns out to be an unfixable problem. Give away cases seems to be the only option...
 
I really wonder at what point someone was thinking "Ok, let's do something innovative with the antenna placement. We've got this cool glass backing now which should definitely improve signal propagation over the previous model's metal backing... but what should we do..." and then having such genius people come up with something that flies directly in the face of microwave radio transmission by giving it something that directly affects said propagation by wicking that energy right into the skin, or causing some grounding that shouldn't be happening.

Anybody with any knowledge of antenna systems (mine is nowhere near as in-depth as others but I have a copy of the ARRL Antenna Book on my shelf right beside me) would tell you "Don't touch the antenna, if you do you're gonna screw it up" as I noted earlier. Man, this is so mind bogglingly absurd I can't really find the words for it. ;)

People sticking with the "ok, so I won't grip the whole phone like I did in the past" aren't apparently realizing it's happening even with just a fingertip - a single fingertip - in that one seam bridging those two points and it's all over, for the most part. And the 'rubber band' case providing precisely the required solution for this precise situation... nah, I'm not buying it, and I don't mean the iPhone. :D

And here I was thinking I was getting too old to be surprised much anymore...

I made a prediction that within 2 weeks (15 days or so) Apple will probably start giving away the bump cases to any registered iPhone 4 owner (gotta prove ownership) upon request. We'll see how that prediction works out but I'll say this:

If they do start giving them away, even within the next month, I'll consider my prediction and the thinking that led up to it entirely accurate. I believe this was all considered, dreamed up, planned, and put into action months ago when they "discovered" this issue and had to scramble for a very specific solution (the bump case) because they couldn't start over from scratch, it was simply way too late for anything like that.

Wow... I'm just really stunned over this...
 
that would be believable if there weren't reports of entire loss of network connectivity and non response on voice calls.

Which are pretty much run of the mill Internet complaints about AT&T's network: service unavailability in supposedly covered areas and dropped calls.

Doesn't really constitute proof of a design defect on the iPhone 4, despite the runaway conclusion this thread seems to have reached overnight.
 
If they do start giving them away, even within the next month, I'll consider my prediction and the thinking that led up to it entirely accurate. I believe this was all considered, dreamed up, planned, and put into action months ago when they "discovered" this issue and had to scramble for a very specific solution (the bump case) because they couldn't start over from scratch, it was simply way too late for anything like that.
Or maybe they'll do nothing and let people throw them another $30 for a working phone... I can't help but be curious whether that would actually affect people's attitudes toward them or not.

Edit:

Doesn't really constitute proof of a design defect on the iPhone 4, despite the runaway conclusion this thread seems to have reached overnight.
Well if we say there's no defect, there's really not much to discuss. Still just speculation. I'm not totally convinced yet, but the body of evidence is certainly building up rapidly. I'm also open to any explanation that would cause a signal strength display problem that only manifests itself when your hand is touching certain parts of the case. That's far more implausible to me than an actual signal quality issue, whether it's caused by the new antenna's exposed surface or some other RF design flaw.
 
If it only occurred in specific very precise situations - meaning holding the phone - I might tend to agree to some level with Terpfen, but that's not the case as the video evidence so far that I've seen has shown.

There's a big difference between a full on "gorilla grip" on the phone and simply skin contact as indicated by several videos where people put the phone on a bed or a table-top or some other flat surface and got a 4-5 bar signal. Afterward they would simply apply one fingertip to that area on the lower left side bridging the two antennas meaning their skin is acting as a conductor between those two surfaces and wham, there goes the signal, in some situations a total loss of service after 10-20 seconds.

If they happened to actually hold the phone by applying a finger to each lower side effectively bridging both of the gaps - left and right - the signal disappeared even faster.

In this situation where skin contact alone is degrading performance so drastically, something is terribly wrong here.

There's just no other logical reasoning that anyone can probably come up with. Even holding the phone along both sides with just the fingertips without bridging that gap isn't having nearly the effect that covering that gap and "completing the circuit" is. That fingertips on the sides grip IS having some effect, given the nature of microwave propagation in organic tissue because of direct contact and the skin's capacitance, but nowhere near as bad as closing that gap does.

As such, that's enough "evidence" to definitively call a manufacturing defect, unless of course Apple has some support/KB article that says "Oh yeah, we know about that, it's designed to work that way. Solution: buy the bump case and your problem is solved."

And I love it when people just keep calling it 'a black line' because it's a GAP in there, a hole essentially between the two metal parts of the chassis framing, but I get their meaning. I just find it funny they keep treating it like it's a line of paint in the metal - do these people not realize the iPhone's antennas are separate pieces of metal, at all?

Geez... I made a comment that if it were any other product this would be all over the place by now, and Apple seems to get a pass when such things crop up and I've never been able to figure out why.

Let's see what happens in the next few days...
 
put a strip of electrical tape around it... hahaha! There are lots of colors to pick from too...

(If anyone actually does this ghetto mod, please post pictures!)
 
This is a hardware issue, no firmware can fix that... I hope a recall is in order.
I don't like cases, bumpers or protective films on any of my iPhones, I like to hold it bare.

This issue would really suck for me... Would turning off WiFi, BlueTooth, FM solve the cross-antenna issue?
 
Every phone I've had in the last 5 years, iPhone, Blackberry, etc would reduce signal when held and gain signal when put on a desk. People are just looking at ANYTHING on the new iPhone. From those I know with the new iPhone it's no worse than the other phones.
 
When a phone you hold in your hand suffers such a dramatic loss - and reproducible - of performance just by contact with the skin, well... how clear does it have to be?

My only hope (aside from Apple actually admitting this could be and most likely is a defect in design and manufacturing) is that people will NOT let this slide by, seriously. I've already seen hundreds of posts by the naysayers that simply cannot abide with Apple doing anything wrong or ever making a product that's not 100% perfect from out of the box till it's considered obsolete when the next generation model comes out.

If the thousands of posts I've read overnight across 20+ forums and several news websites as well as the 100+ videos I've seen aren't enough proof to sway even the most diehard Apple fanatic that something is quite wrong with this phone, then "The Cult of Mac" has far more control that even I dared imagine.

I will state that it could be - that's COULD BE an issue tied directly to specific factory runs of this phone - that's something I have to admit and state as a possibility right here and now, but the reports I've been reading have come from countries in pretty different parts of the globe so, I can't imagine a guy in San Francisco would have an iPhone 4 from the same batch as a guy in the UK.

If it's a specific stepping or internal revision of the device and this issue or flaw is specific to those only, so be it, but so far the evidence I've seen says this is going to become a major problem today and for the time being. If not, fantastic, have fun with your new iPhones.

Something tells me it's not quite that simple this time, and Apple knew it ahead of even the introduction at WWDC - they had to. I mean really, use common sense and put 2+2 together for a change:

An issue tied directly to the metal chassis/antenna band because of contact with the skin and they introduce a "case" that only covers/protects the band so nothing can come into contact with it, most notably skin?

Brilliant engineering coupled with marketing genius at the last minute because it was too late to retool the entire product to fix the problem, I tell you. Coincidence? Like hell it is.

And for those folks saying/claiming other phones do the same thing(s), I'd sure love to see any other cellular phone lose a signal and outright lose service totally just by touching it with a fingertip while the phone is laying flat on a table and stationary because I've seen 15+ videos of that demonstration with the iPhone 4 and they all suffer the same flaw.

Anybody? Anybody? Any other phones that do that? No? Didn't think so. How much proof does someone really need to break that Cult programming? I wonder.

I'm going to bed, but I expect to see a ton of info and reports about this all over the place when I get up late this afternoon... ;)
 
My blackberry definitely doesnt lose signal when I place one finger on it's lower left side. It's a design flaw. Whether or not it turns out to be an actual problem, or just something for us geeks to bitch about for a while, remains to be seen.

This is coming from a guy still trying to get his hands on an Iphone 4.
 
Ok, so here's something to consider with my scientific (lol) testing.

At home, I normally do not get even decent recption. My girlfriend has an LG Xenon, and I had been using the iPhone 3G for the past 2 years. We're lucky to get 2 bars if the phones are left on a table, and 90% of the time, they're on EDGE. So, at home, after seeing these posts and the videos, I tried it, and sure enough, the 2 bars decreased down to 1, then down to No Service. As I mentioned above, if I held it by my thumb on the left side, and two fingers on the right, I would consistently get 2 bars, whereas I normally wouldn't even get that with my 3G.

So, I'm at work now. I get excellent reception here at the office. I am on 3G with full service. I am grabbing the entire phone by the left and right side, and not a single dropped bar. Full 3G service still. From my evaluation, in a poor service area, this will happen as the lone signals the phone is able to grab gets diminished too much, but in a good service area, there's plenty of signal for it to get through one's hand and whatever interference is happening.

*shrugs* I'm really happy with it.
 
Does Poor iPhone Design Cause Dropped Calls?

The thing is, your hand is actually pretty radio-transparent, as it's full of gaps and isn't hugely dense--the radio waves from the antenna should be largely unaffected by a nearby limb. The difference with the iPhone 4 though is that you can actually touch the electrically-connected radio transmitting antennas themselves. You have to, really, if you're holding the phone. Is this going to affect how well they can transmit and receive radio signals? The answer is a definite "possibly." Because your body is weakly electrically conducting, and the interaction between your hand and the phone's metal antenna may indeed affect how it transmits radio waves. It's even possible that the lower-left corner sensitivity to being held is due to the user's hand weakly connecting the 3G antenna with the iPhone's other antennas, messing up the 3G signal transmission.

But it's hard to imagine this occurring as seriously as it appears in the videos--and Apple will have (don't doubt it for a minute) conducted extensive scientific and real-use tests on such a significant design feature. And with Cupertino's love of high-precision, it's unlikely they'd have let such a serious design flaw through. And from a raw physics point of view it doesn't really add up.

So what is really going on, if anything? In regions where users have weak connectivity to nearby phone masts, it's plausible that signal attenuation from user's hands will affect signal strength to the point of affecting call quality. This really should be in the fringes of the signal from the antenna though--so maybe Apple's software is incorrectly displaying signal strength, and is actually overly-sensitive. Those users seeing three bars of strength drop to none may actually be equivalent to just one bar dropping away, in other words. We know that Apple's had software issues relating to the signal display systems before. With a patch (to tune the signal strength display to the particular performance of the iPhone 4) this will be less noticeable. It's also possible that some slight discrepancies in the manufacture of different iPhone 4s are affecting how sensitive to antenna interference each unit is. With the antenna exposed, this may be a more pronounced issue than in earlier designs.

And one last thing: Don't forget that this isn't necessarily a new effect. As MacRumors notes, similar effects have been demonstrated on earlier edition iPhones for years, and nobody's made much of a fuss about it. Gizmodo does, for one reason or another, have a bit of an axe to grind against Apple at the moment ...
 
I seem to recall similar issues with the 1st generation iphone...
if you covered the plastic antenna area, it would drop calls also.
 
Again, I'm unable to reproduce this here in a full-service area, but now people are isolating it to the bottom left corner.
 
It's definitely a real problem. If I hold my phone with my bare hands, a reception bar ticks away every two seconds until I'm at 1 bar or "searching." If I wrap the edges of the phone with my shirt and hold it, I do not lose any reception bars. I've tested this multiple times. I don't really care though. I'll be getting a case for it soon and it won't be a problem for me.

It shouldn't be a problem in the first place though.....take it back and complain so you can get the product you paid for, why bend over and accept it ....
 
I cant even get it to happen if I am trying to. Most mines dropped when I picked it up was a bar or two but it went right back up.
 
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