August 31, 2007

"Alright, who left their cell phone on?"
— Gabriel Malor

Over at Gizmodo, there's a gif of lighting striking a plane taking off from Osaka. As the fellow says, this happens all the time; the lighting just passes around the plane.

He asks a question that I've always wondered about:

Now, can anyone explain to this ignorant (me) person how 100 trillion (million million) watts can hit a plane and nothing happens to the electronics inside, while my cell can wreak havoc emitting just a few microwaves?

I'm sure someone here knows, so, what gives?

(Oh, and yeah, I'm sure that gif is a zillion years old. Don't start with me. It's late.)

Posted by: Gabriel Malor at 09:24 PM | Comments (88)
Post contains 117 words, total size 1 kb.

1
It says right on the linked page: "Lightning is not dangerous for airliners, as the electricity flows around their aluminum skin."

Posted by: Nobody at August 31, 2007 09:28 PM (3H6in)

2 Best comment in the Gizmodo thread? This one.

Posted by: Patton at August 31, 2007 09:36 PM (tNl8g)

3

The lightning passes harmlessly around the anodized aluminum frame of the aircraft.


All the people inside, however, are incinerated instantly. 


Posted by: See-Dubya at August 31, 2007 09:53 PM (1gdFs)

4 The airframe itself works as a Faraday shield along with static wicks that direct the electrical current off the surface, protect most of the interior components of the aircraft. 

Posted by: lowandslow at August 31, 2007 10:11 PM (UiYsk)

5 Um, yeah. I know all that...as I mentioned in the post. My question has to do with cell phones and other electronics in planes.

Posted by: Gabriel Malor at August 31, 2007 10:15 PM (1Ug6U)

6 I'm not really familiar with all the electronics in airliners just small general and commercial aircraft and I can tell you this, they don't bother any of the avionic or other electrical components on those. I doubt they have any effects on the airlines either, I think this is a hold over from radiotelephone systems from years back.

Posted by: lowandslow at August 31, 2007 10:23 PM (UiYsk)

7 I should add, I'm not aware of any Federal Regulations prohibiting the use of cell phones or computers, gameboys, etc. in any aircraft during takeoff or landing. I think this is  just airline policy.

Posted by: lowandslow at August 31, 2007 10:28 PM (UiYsk)

8 I checked and there is a Federal Aviation Regulation (FAR 91.21) on using electronics and it only applies to the airlines, all other aircraft operations can use them as long as the pilot determines they're not going to interfere with the avionic.

Posted by: lowandslow at August 31, 2007 10:55 PM (UiYsk)

9 If cell phones were dangerous, how come there's never been a plane crash caused by them?  Are we really supposed to believe that no one has ever left their phone on in the last 15 years?

Posted by: Mrs L at August 31, 2007 11:49 PM (FOLZe)

10 I do know that cellphones can mess with infusion pumps in hospitals, such that they can trigger the pump to just dump in the drugs that they were supposed to only drip into your bloodstream a bit at a time. An added problem with cellphones is roaming. When your phone can't connect to a cell, it starts sending pings until it finds one. (Incidentally, this is why your cellphone batteries don't last as long if you're inside a large building or way out in the boonies.)

Posted by: Cybrludite at August 31, 2007 11:53 PM (XFoEH)

11
#5 Gabriel Malor



The "cell phones and other electronics" are IN the planes. The electricity flows around the OUTside of the plane. That's the short form.



The long form is that lightning is direct current (instead of alternating) so it obeys Gauss' Law. Like charges repel each other, so they go to the extreme distance apart -> to the outer surface of the plane.



Automatic, natural protection.




Is anyone else watching ESPN's coverage on Virginia Tech's upcoming football game? They're being very coy about showing the list of victims in the lunchpail. Is the murderer's name on that list?


Posted by: Nobody at September 01, 2007 12:29 AM (3H6in)

12 Cell phones don't adversely affect the avionics one bit in a commercial airliner.  Or any of the other electronic doo-dads.

The regulation was put in purely as a way to increase revenue for the airlines--No, you cannot use your cellphone, but here, use our safety-tested AirFone for only $3.99 per minute...

The only way shutting them off during takeoff and landing increases safety is that those are always the most dangerous times of any flight, and if you're yakking on a phone, you won't hear the pilot's instructions, or more likely, pay even less attention to them or the flight attendants announcements than you usually do.



Posted by: Hurricane Mikey at September 01, 2007 12:56 AM (v47Mt)

13 I refer you to the IEEE: http://www.spectrum.ieee.org/mar06/3069
They found an incident where a DVD player caused a 30 degree error in navigation systems. The basic summary is that RF emitting devices such as the cell phones can intefere with GPS and stuff.


Posted by: ultimaflare99 at September 01, 2007 01:22 AM (waqbN)

14 Lightening is a natural phenomenon and is thus harmless. Cellphones are the manmade creation of the McChimpyHitlerBurtonTrilateralMasonKKKarlSkull&BonesCheneyExxon Lockheed™ Military-Industrial complex, and thus are very very harmful to those airplanes. And they cause global warmening. And global warmening worsens the effect the cell phones have on the planes. It is a vicious cycle of conspiracy.

Posted by: Tushar D at September 01, 2007 02:23 AM (9ULFg)

15

An airplane is a closed Gaussian surface. There's no way for a current to pass into the plane from that surface. In fact, the charge from a lightning strike is unable to persist on that surface; it will bleed away into the surrounding air very quickly. Your cell phone, on the other hand, has the capacity to interact with navigation and fly-by-wire systems inside that surface.


 


 


Posted by: Francis W. Porretto at September 01, 2007 02:35 AM (PzL/5)

16 FWIW, the Mythbusters guys tested this and while they were able to mess up some old surplus avionics mounted in a rack to a degree they were unable to cause any problems even on a small private jet with the phones' transmitters amplified to well beyond normal levels.  Not that I'd trust my life to any of their results, but it's more data than whoever wrote the relevant laws gave us.

It's probably more a combination of paranoia by the government and the fact that a phone moving at 500+ MPH relative to the ground is going to play holy hell with the carrier's network since you'll be switching cells almost continuously.  The fact that the 9/11 planes were able to make workable calls is impressive (but not impossible - sorry Truthers), but I wouldn't want to impose that kind of stress on the networks on a regular basis.

Posted by: Ian S. at September 01, 2007 02:40 AM (pg/HS)

17 Bingo! Ian S. comes closest to the right answer. The ban was implemented at the request of the cell phone carriers. A cell phone will attempt to register with multiple base stations (across multiple carriers) and this causes problems with their billing algorithms.

Posted by: profligatewaste at September 01, 2007 02:51 AM (egIwj)

18 Lightning will at times burn a hole into a plane.
As for cell phones, if there was a crash even if the cell had nothing to do with the accident the lawyers will come out of the woodwork looking for the deep pockets.

Posted by: jon spencer at September 01, 2007 03:57 AM (Jnfau)

19

"billing algorithms" , "closed Gaussian surface" , "RF emitting devices" , "infusion pumps" , "Faraday shield" , "lightning is direct current" , "static wicks" , "anodized aluminum"


What happened to the moronblog?


Posted by: John F Not Kerry at September 01, 2007 03:58 AM (4gHqM)

20

OT: I lost the "Open Blog" instructions I got a few weeks ago (yes, I delete ALL my emails), but I wanted the morons here to see that there are people (even adults) who don't even measure up to the intellectual prowess of Miss Teen South Carolina: http://www.youtube.com/watch?v=KxmHEGy7JUU


Bloggers or open bloggers, feel free to post this so everyone can see it. I found it at www.Rachellucas.com .


Posted by: John F Not Kerry at September 01, 2007 04:22 AM (4gHqM)

21 Lighting? Gif? What is this, the hood?

Posted by: ricpic at September 01, 2007 04:22 AM (0kHZW)

22

Lightning is white noise, no actual signal.  Radio receivers in the plane won't receive anything that is intelligable, so, won't act on anything.  The signals transmitted by cellphones --could possibly-- be on the same frequency with the same modulation technique as avionics on the plane.  Odds of anything happening are very low, but not impossible, and they're just being extra cautious/paranoid.


Posted by: Mark in Portland at September 01, 2007 04:33 AM (kFHYM)

23 Not to turn this into a pilot blog but has anyone heard of a pilot who had radio/electrical problems using their cellphone to call the tower or approach facility while in flight?  I could never remember the damn light gun signals, so I think if there wasn't a non-towered field near by, I'd rather do that than take my chances going in to a controlled field NORDO.


Posted by: Drew at September 01, 2007 04:45 AM (hlYel)

24 How about maybe for the few hours I'm stuck in a plane with you morons, I'd rather not hear your fucking inane cell phone babble?

Posted by: kev at September 01, 2007 04:46 AM (c6zR0)

25 The EMI, both frequency and amplitude, coming out of some consumer electronics is truly incredible.  I'd be surprised is some of it even passed the weak FCC consumer electronics requirements.

The problem has gotten worse with "modern" electronics containing embedded microprocessors, shoddily designed boards, and insufficiently shielded housings.

I have a cheap Chinese DVD player that emits VERY STRONGLY and very broadly across commercial A/M bands.  It will mess with a radio playing 30' away on the other side of the house.

I also suspect, many manufacturers are submitting "special" samples for FCC cert that have been hand manufactured and shielded to pass.  When the cert is issued, the mass production units drop the shielding as a cost cutting measure.

Posted by: Purple Avenger at September 01, 2007 04:51 AM (NiDeC)

26 The ban was implemented at the request of the cell phone carriers.

That might explain cellphones over the last 10 years or so, but the "turn off all electronic devices" instruction goes way, way back before cellphones.  I remember having to turn off my walkman in 1986.

So why do I have to turn off my iPod?

Posted by: Bender Bending Rodriguez at September 01, 2007 04:53 AM (nDf7u)

27 cellphones --could possibly-- be on the same frequency with the same modulation technique as avionics on the plane

Cell phones don't operate on a single frequency.  They hop frequencies. 

So sayeth the Wikipedia:

The most celebrated invention of frequency hopping was that of actress Hedy Lamarr and composer George Antheil, who in 1942 received patent number 2,292,387 for their "Secret Communications System." This early version of frequency hopping used a piano-roll to change between 88 frequencies, and was intended to make radio-guided torpedoes harder for enemies to detect or to jam.

Yep.  Hedy Lamarr, once voted the most beautiful woman in the world, helped invent cell phones. 

The same spread-spectrum technology that keeps cell phones from interfering with each other pretty much eliminates any possibility of interference with avionics. 

Posted by: Phinn at September 01, 2007 04:59 AM (eD51V)

28 In part the regulation is a hold over.  Earlier models of cell phones operated in frequencies that were shared with aeronautical radionavigation systems.  They also were more inefficient so the output more power, thereby increasing the possibility of problems.

There are still some similar problems today, this last week I was testing a device that uses an 802.11a card so I had to look at all frequencies of interest up to 30 GHz and everything was going fine up until I got up above 1.4 GHz suddenly there was a huge spike on the spectrum analyzer  at a particular frequency.  Turns out a Marine Corps helicopter had just flown overhead and we were in a band that was used for radionavigation when we went back and looked again I still had a frequency of interest but with the helicopter gone it was reduced by about 12 dB.  If I had been operating in that helicopter it could have been problematic. 

That's one reason the 802.11h standard was adopted at the insistence of the EU and why the FCC won't approve new wireless devices in the 5.2 to 5.7 GHz range unless they implement Dynamic Frequency selection and Transmit Power Control.

Posted by: chad at September 01, 2007 05:01 AM (WNcvq)

29 The thing is, it doesn't have anything to do with the amount of "juice". The reason cell phones can (but not necessarily "do") interfere with electronics has everything to do with the frequency at which it's operating. The electromagnetic waves at the high frequency used by cell phones can induce a current in electronics.

Posted by: dorkafork at September 01, 2007 05:02 AM (kErJj)

30

I don't need a cell phone on a plane.  I make calls with my mind.


Radar love baby.


Posted by: Dave in Texas at September 01, 2007 05:04 AM (pzen5)

31 @ purple avenger

You are right on the lack of compliance with the FCC standards.  I test this stuff all the time and most off the shelf gear wont pass.  TVs and DVD players are horrible emitters, Computers too.  If i am going to use them as support gear I have to copper tape the hell out of every seam in order to keep them from interfering with my system.

Posted by: chad at September 01, 2007 05:05 AM (WNcvq)

32 How about maybe for the few hours I'm stuck in a plane with you morons, I'd rather not hear your fucking inane cell phone babble?

kev,


My thoughts EXACTLY.  Most cell phone conversations are completely unnecessary and, to anyone other than to two idiots talking, an aural nuisance.


The last thing I want to do after being delayed at the gate for an hour and sitting on the tarmac for another hour is listen to some fucking jackass make a riduculous work call so he can discuss the world's most important marketing plan ever.


Sit down and shut the fuck up before I ram that Bluetooth ear piece down your throat you fucking moron.


I hate cell phones.


Posted by: Rosetta at September 01, 2007 05:07 AM (omkIU)

33

This goes back further than most people assume.  Wilbur's last instructions to Orville were "Watch your airspeed, and turn off that fucking cellphone!"  They swore like sailors any time their father was not around.


Glad I could help.


Posted by: sherlock at September 01, 2007 05:08 AM (ojW85)

34 At the very least, cell phone users shoulde be made to go outside, more than 20' any door.....just like smokers.

Posted by: GarandFan at September 01, 2007 05:40 AM (G1NrV)

35 There are some things you Earthlings are not supposed to understand.

Posted by: 1sttofight at September 01, 2007 05:42 AM (gs87a)

36 Two things to be concerned about with an airborne lightening strike:
1. Leaking fuel or fuel vapor - very combustible when at the aircraft skin surface. Remember the airliner that caught fire from a small fuel leak after landing in Japan recently.

2. Structural damage - I've seen a 3 ft. chuck at the top of the tail of one jet missing after a lightening strike. It may have been structurally weakened from corrosion or something, I don't know.  You never know what can happen.

Posted by: sammy small at September 01, 2007 05:49 AM (DbEIX)

37 Computers too.  If i am going to use them as support gear I have to
copper tape the hell out of every seam in order to keep them from
interfering with my system.


Chad, I know of a fellow who is big into ham radio and he uses ancient IBM PS/2 microchannel bus machines for the support stuff because they are very well shielded and don't mess with stuff.   If you don't need a lot of compute horsepower, using an old PS/2 Model 80 or Model 95 might save you a lot of grief.  You can get'em for a song these days.  Avoid the Model 35/40(these are ISA and inherantly noisier), 55, and 65 though.  Those all have the evil Dallas chips as clocks whose internal batteries are all dead by now.  New DS1287's are made out of unobtanium -- you'd have to rework the old chip, which is doable, but a somewhat of a PITA.  The Model 80 uses a common 6V lithium camera battery, and the Model 90/95 use a common Sony CR2030

IBM had a very extensive EMI test lab in Boca.  Those PS/2 machines were better than the FCC requirements because IBM knew they'd be getting used in lab installations.

Posted by: Purple Avenger at September 01, 2007 06:04 AM (NiDeC)

38 .23 Not to turn this into a pilot blog but has anyone heard of a pilot who
had radio/electrical problems using their cellphone to call the tower
or approach facility while in flight?  I could never remember the damn
light gun signals, so I think if there wasn't a non-towered field near
by, I'd rather do that than take my chances going in to a controlled
field NORDO.

Good luck trying to find a Control Towers telephone number, I think the only place I found them listed was in the AOPA directory.  The last time I did go in to a tower field without a radio the guy in the tower said "sure come on in, I'll give you the light, if I can find it. If you don't see the light come in anyways."





Posted by: lowandslow at September 01, 2007 06:31 AM (UiYsk)

39

Sit down and shut the fuck up before I ram that Bluetooth ear piece down your throat you fucking moron.


My, my, my, a little feisty this morning. Are we not getting any?


Posted by: pajama momma at September 01, 2007 06:52 AM (Tbl5c)

40 >>Are we not getting any?

Oh he is getting lots. Just not the kind he wants. Girls chase Rosetta, but s/he pines for boys.

Posted by: Tushar D at September 01, 2007 06:57 AM (9ULFg)

41 Ah, that's why we had all the toe tapping videos last night. He did know exactly how to find them didn't he?

Posted by: pajama momma at September 01, 2007 06:59 AM (Tbl5c)

42 Since Faraday has already been mentioned, I'll just say "what he said." This is, incidentally, also the reason why the safest place to be if you're caught outside in a violent thunderstorm is inside your car (just keep your paws off the chassis).

As to the horrible dangers of cellphones in planes and hospitals, suffice it to say that I have not heard of a single incident where a cellphone caused anything untoward to happen, not to mention that today's electronics are a long shot from the crappy shit we had 10 years ago. Still, it's a case of "better safe than sorry" and, besides, people who can't keep their idiot cellphones off in a hospital or on an airliner ought to be treated in the same fashion as morons who have to have the damn things on in movie theatres and restaurants: Drag them outside and beat them to death with the damn things.

Posted by: Misha I at September 01, 2007 07:01 AM (amSaq)

43

Aha! I wondered why new cellphones keep getting smaller.


Posted by: Calix at September 01, 2007 07:49 AM (8d3U/)

44 @Misha

I will try and dig up the story but there was just an article in one of the national papers about cell phones interfering with heart monitors at hospitals. 

@ Purple Avenger

Thanks for the tip, unfortunately that isn't an option for me but I will keep it filed as a good to know in case I can use it in the future.  This is just one of those things where the regulations say one thing but everyone (except me) ignores them because they know that the chances of anyone calling the FCC and complaining about a piece of gear is slight.  I on the other hand have the possibility of an OEM customer running a verification test in their chamber or open area test site and I better pass or be so damn close it can be account for in the acceptable differences that exist between all sites and the measurement uncertainity errors,  and then I better be able to go make it pass without having to completely rebuild the box or come up with some completely unrealistic configuration. 

I won't mention the company I work for but from what I have seen at various test labs we are among the very few who take that approach.

Posted by: chad at September 01, 2007 07:50 AM (WNcvq)

45

My, my, my, a little feisty this morning. Are we not getting any?


PajamaMomma is attractive and looks a lot like the girl who gave me the hand job. I forgot to mention that it was in a KFC bathroom in a mall.


pajama momma,


Do you have any plans to be at KFC in the next few hours?


 


Tushar,


YOU had some good moves as a young man.  What happened to you?


Posted by: Rosetta at September 01, 2007 07:52 AM (omkIU)

46 I've tried on several occasions to send a text message while on a flight, and I've never been able to get a signal.  I always wondered how the people on the 9/11 flights were able to do that... might have something to do with being low and still in a large city I guess.

As to jackasses talking on their phones on the plane.... I was on a flight a couple of months ago and there were two guys four rows back, in adjacent isle seats.  One guy started talking shop in full voice to the other before we took off.  After about 15 minutes it hadn't stopped, so I put down my book, and plugged into my ipod with noise canceling earbuds (which are the Bomb).  Three and a half hours later I pull them out, and the guy has not even slowed down (I had taken the earbuds out a couple times when letting people out to use the bathroom)!

The moral of my tale?  You don't need a cellphone to be an inconsiderate a-hole.

Posted by: Terry at September 01, 2007 08:01 AM (/Soh5)

47

You don't need a cellphone to be an inconsiderate a-hole.


Terry,


Your statement is true but somewhere there exists a Venn diagram that shows that, while only a small percentage of inconsiderate asshole behavior is cell phone related, most cell phone behavior is inconsiderate asshole related.


It seems, cell phone or not, that the louder someone talks, the more inane their conversation.


Everyone should just shut the hell up.  Always.  Even me.  But especially non-me people. 


Posted by: Rosetta at September 01, 2007 08:17 AM (omkIU)

48 Forty-seven comments and no one's mentioned "Lightning Bolt! Lightning Bolt! Lightning Bolt!" yet. Is this still Ace of Spades?

Posted by: DSkinner at September 01, 2007 08:37 AM (FzR6w)

49

pajama momma,


Do you have any plans to be at KFC in the next few hours?


Come on now Rosie, what do you need little ole me for? The girls are chasing you, remember?


Posted by: pajama momma at September 01, 2007 08:40 AM (Tbl5c)

50

"Lightning Bolt! Lightning Bolt! Lightning Bolt!"


I love the Chargers!!!


Posted by: pajama momma at September 01, 2007 08:42 AM (Tbl5c)

51 Hey Ace,

This is because the skin of an aircraft is thousands of times more electrically conductive than anything inside, thus creating a "Faraday Cage".  The potential travels on the exterior of the conducting body. 

Check this out for real in this video:

http://www.youtube.com/watch?v=HcalasGr_uk

--Bill


Posted by: Bill Wangard at September 01, 2007 08:50 AM (Lg0RO)

52 not to mention that today's electronics are a long shot from the crappy shit we had 10 years ago

The products today are much worse than 10 years ago regarding EMI with the profusion of Chinese made stuff and relatively non-existence of spot compliance testing. 

Its been years since I've seen a plastic bezel or cover for a PC that had vacuum plated shielding. 

Turn on some gadget today and its like a nuke EMP going off.

Posted by: Purple Avenger at September 01, 2007 08:54 AM (NiDeC)

53

Come on now Rosie, what do you need little ole me for?


I've heard you have mad skillz!!


 


On a separate but related note, if Ace cared about us he would have live-blogged Larry Craig's resignation from a men's room somewhere.


Posted by: Rosetta at September 01, 2007 09:04 AM (omkIU)

54

Turn on some gadget today and its like a nuke EMP going off.


If only...


Posted by: Entropy at September 01, 2007 09:07 AM (HgAV0)

55 Roseetta,

Ace couldn't live blog in the men's room because it is full of cops trying to sting all the straight guys.

Posted by: larry craig's former aide at September 01, 2007 09:14 AM (PlKAK)

56

Frequency hopping is exactly why I wouldn't want celphones active on a flight.  Depending on how the freq's are rotated, you can hit 10's of thousands of freq's, and depending on the power of the transmitter, a momentary blip every couple of seconds interfering with something, or several somethings is an uncomfortable thought while on a plane.


A guy I worked with Jim, said he left his blackberry on while he was flying one time, he just forgot to turn it off.  He said throughout much of the flight he kept hearing a click, and he was getting uncomfortable thinking something wierd was up with his part of the plane.  After a while he realized that it was the speaker on his blackberry clicking to some of the EM in the Airplane.


Posted by: Wickedpinto at September 01, 2007 09:19 AM (QTv8u)

57 Ever have your cell phone set off a security alarm at circuit city or best buy?  Ever have your cell interfere with the stock radio in your 83' caprice?  we are surrounded by em, and I think there is still a lot of "FM" to it.

Posted by: Wickedpinto at September 01, 2007 09:21 AM (QTv8u)

58

100 trillion (million million) watts


I think they meant.


1.21 gigawatts.


Posted by: Wickedpinto at September 01, 2007 09:27 AM (QTv8u)

59 [insert mental picture of pilot trying to nav to the nearest field using his cellphone after the radio packs it in under IFR conditions]

Cellphone to call the tower in case of radio failure? Next time, spend your money on a handheld radio and comm with them that way. You usually get VOR features with the handheld to boot and it's a win-win situation all the way around, even if your third-prty publications (like the FlightGuide I used to carry) have the field phone numbers.

On a closely related note, as one of Light Plane Maintenance's sister publications pointed out years back, any device that receives through an antenna can also inadvertantly transmit over it if you're at a resonant frequency (or harmonic thereof) and vice versa. That includes cellphones, handheld GPS devices, etc., etc. And damned if I'd trust some non-professionals (read that to mean Mythbusters) to tell me whether something's a problem or not in this regard, considering the stakes. They aren't trained avionics technicians by a long damned sight. *Now*, considering that if the physical impact doesn't kill you in a plane crash, you often end up burning to death, turning off your frigging damned electronics to avoid interference with the pilot's all critical navigation hardware is a small price to pay.

Last but not least, sure, some parts sometimes end up blowing off the plane during a lightning strike, Faraday cage or not. But you find that frequently, they're the tail or nosecone parts, made of plastic or fiberglas, which don't carry charge over their skins like metal. Why do y'all think that homebuilt kit plane makers are required to lay metal mesh underneath the fiberglas skins of their planes?

Man, moronblog indeed.

Posted by: Additional Blond Agent at September 01, 2007 09:39 AM (DQDJU)

60 The issue is liability. An airline can say "act of God" if something bad happens because of lightning but if they allow passengers to use electronics and something happens that can in any way be traced to instrument problems, rest assured the lawsuits will fly to new heights and the insurer will probably hang the airline out to dry. It's all about risk averse corporate behavior. The actuarials decide that the odds of an event versus the inconvenience to the passengers don't balance and that's the end of that.

Posted by: TBinSTL at September 01, 2007 09:41 AM (2J6+t)

61 Jigawatts.  In the manner of Jenghizz Khan


Posted by: OregonMuse at September 01, 2007 09:44 AM (5UgG/)

62

I've heard you have mad skillz!!


I do have skills...........you know, like nunchuk skills, bow-hunting skills, computer hacking skills.


Posted by: pajama momma at September 01, 2007 09:57 AM (Tbl5c)

63

The lighting strike doing damage is like the kinetic laser concept.  That much energy produces a kinetic force.  It ain't JUST the electricity it's all the photons, and other energetic particles, as well as other matter responding to that energy that can create a sort of physical punch.


Posted by: Wickedpinto at September 01, 2007 09:58 AM (QTv8u)

64 It isnt a problem of wattage.. Its a problem of frequency harmonics.

If a radio transmits at say, 145.470 Mhz (a ham radio frequency), a nearby radio receiving at any multiple of that frequency will receive interference.  Since cell phones operate at the Gigahertz level, they can and do interfere with other types of electronics.

Posted by: cadetwithchips2 at September 01, 2007 10:23 AM (MswJ8)

65 As several previous commenters have noted, it's only a small percentage of the existing consumer electronics which can cause interference with avionics, either because of manufacturing defects or post-sale damage. Although modern airliners do have shielded electronics and wiring, connections do work loose over over time, wire insulation abrades, etc.

Most airliner crashes are caused by more than one unlikely problem occuring on the same flight. If a faulty cosumer electronic device is used on an airliner with a flaw in its shielded electronics, then inteference could be caused in the avionics. By itself, such interference may not be much of a threat at high altitude in the middle of the flight, but if it occurs while the pilot is navigating by instruments while flying close to the ground, that's another story.

Banning consumer electronic device usage just after takeoff and just before landing (or if the pilot suspects interfence at other times) is a risk-reduction measure to try to elminate one of the "more than one unlikely problems" that could lead to a serious accident.

Posted by: Siergen at September 01, 2007 10:38 AM (bxCXv)

66 I've been on a plane hit by lightning. The storm itself was really bad and that is the only time I've ever really thought "We're all gonna die." Then the lightning hit. And needless to say, we didn't all die. Scared the piss out of everyone and made some cool burn marks on the plane.

Posted by: Pablo at September 01, 2007 11:10 AM (yTndK)

67 This technical shit is making my head hurt.

On to the next topic!

Posted by: Bruce at September 01, 2007 11:27 AM (2q+Ss)

68
I was hit by lightning when I was 19. Hurt like hell but it sure makes for a cool story. Don't know why it didn't kill me. Any thoughts?

Posted by: Steve (the artist formerly known as Ed Snate) at September 01, 2007 11:33 AM (o11Pg)

69

I round every day in an ICU and every person on the team has a cell phone turned on and using it actively within the unit. 


Not a single incident to report.


Posted by: KelliPundit at September 01, 2007 11:40 AM (njray)

70

were you sweaty?  Like a runner kinda sweaty?  I heard that as an explanation.  Basicaly you feel like you are on fire, then you go into shock.


I was across the street from an "electronic eye" for a traffic light that got hit by lighting.  The sound put me on my ass and scared the shit out of me.


Nothing like actually being hit though.


Posted by: Wickedpinto at September 01, 2007 12:31 PM (QTv8u)

71

I do have skills...........you know, like nunchuk skills, bow-hunting skills, computer hacking skills.


You're just jealous because I've been chatting online with babes all day.


Also, you forgot trampoline skills.


Posted by: Rosetta at September 01, 2007 12:54 PM (omkIU)

72

Considering that I just applied for a job that requires a LOT of traveling to customer sites, this is a great thread.


RFI can crop up anywhere. Before the IBM PS/2 line, a very popular computer for hams was the original Atari 800 due to its exceptional shielding for a product of its sort. The old Apple ][ machines were horrible. Worse was an early peripheral from Apple, a digitizer pad for graphics. It could knock out TV reception for a block. This was documented as a 'radiation emissions problem' and raised a lot of eyebrows in that era of Three Mile Island hysteria. When the word radiation appeared the assumption was that it must be nuclear associated in some way.


One hassle I run into on long drives is the sound system in my car. To get the feed from my MP3 player (audio books primarily) into the system I have an adapter that goes into the cassette deck. Works great and is a lot cheaper than burning a stack of CDs for a long book. The downside is that the adapter, when in use, acts like a CDMA cell phone antenna, producing horrible noises is a phone is in use within about a 20' radius. I can tell when my phone is about to ring because the interference noise from the stereo precedes the ring by about 3 seconds. Just enough time to pause the book and turn off the stereo if there are no other distractions.


Posted by: epobirs at September 01, 2007 12:55 PM (3PQdB)

73

Terry,


Your statement is true but somewhere there exists a Venn diagram
that shows that, while only a small percentage of inconsiderate asshole
behavior is cell phone related, most cell phone behavior is
inconsiderate asshole related.



That diagram wouldn't be hockey stick shaped, would it?


Posted by: Terry at September 01, 2007 01:08 PM (/Soh5)

74 I was just going to say that RF is freaky shit that does freaky shit, not predictable like electricity. But looks like that's been covered already.

Posted by: BOSS429 at September 01, 2007 01:12 PM (XcXLi)

75

A calibrator friend of my was working on a freq gen.  and it wasn't passing cal.


He kept fucking with it and fucking with it, finaly he gave up, and swapped the main board with his test bed/bench whatever.  Suddenly the "bad" freq gen was operating within prameters, and the test bench was in the same parameters.


He wrote up his repair sheet.  "replaced main board, FM."


I don't know if it's common in the real world, but "FM" means "Fucking Magic."  Even though we have more than 100 years experience with it, electricity, electronics RF EMI and all that shit, are still weird fucking things.


Posted by: Wickedpinto at September 01, 2007 01:22 PM (QTv8u)

76 any device that receives through an antenna can also inadvertently
transmit over it if you're at a resonant frequency (or harmonic
thereof) and vice versa.


Don't even need an "antenna" per-se for this to happen.  Electronics can transmit through the traces on the board carrying its internal signals, monitors, cabling, etc.

I personally experimented with this about 20 years ago and observed an ordinary PC's video card (no attached monitor) broadcasting strongly enough to be picked up between channel 6 and 7 on a TV that had a smooth tuner rather than detentes.  I was picking it up from about 30' away quite clearly.

If I'd built a circuit to inject synch pulses into the signal, I could easily have gotten an image that would have synched up on the TV.  The image flipping and rolling on the TV was very obviously the one I'd programmed the PC's video card to produce.

This is why the military uses Tempest qual stuff for their critical stuff -- commercial junk broadcasts like a transmitter.  Anyone with a circuit that can inject the synch pulses can read a computer screen remotely from quite a distance.  My level of "technical sophistication" was a $69 B&W Zenith TV for a receiver...and that was good enough to show the effect very dramatically.

A couple of grand worth of nice hardware could put you in the sophisticated industrial espionage and fraud business very quickly. 

Posted by: Purple Avenger at September 01, 2007 01:26 PM (NiDeC)

77 A broken inductor (if it's large enough and close enough to a reciever) can act as a dipole antenna.

Posted by: Wickedpinto at September 01, 2007 01:30 PM (QTv8u)

78

See, I get the "how does wicked know this shit."  Thing is I dont know most of it, I just remember stuff.


How the fuck does purp's actually know this shit?  Is he the inspiration of the comic guy from the simpsons? or is he one of "The Sleepless?"


Posted by: Wickedpinto at September 01, 2007 01:33 PM (QTv8u)

79

Also, you forgot trampoline skills.


Eeeesh. I will admit, I am a master at drunk trampolining.


Posted by: pajama momma at September 01, 2007 01:52 PM (Tbl5c)

80

You're just jealous because I've been chatting online with babes all day.


Hmmmmmmm, I wouldn't be surprised.


Posted by: pajama momma at September 01, 2007 01:53 PM (Tbl5c)

81

Eeeesh. I will admit, I am a master at drunk trampolining.


BUNK!!!


Posted by: Wickedpinto at September 01, 2007 02:09 PM (QTv8u)

82

BUNK!!!


You have to tell me what that means so I can respond appropriately.


Posted by: pajama momma at September 01, 2007 02:37 PM (Tbl5c)

83 BUNK!!! is a type of bed, pajama momma.  Dur.

Posted by: Rosetta at September 01, 2007 03:36 PM (KotLt)

84 Once you start operating in the GHz or higher range, which is pretty common nowadays even the traces on the circuit board act as pretty efficient antennas.  Add to that the fact that most people follow sloppy design practices and use sharp right angle turns on their traces intsead of a nice smooth curve and you have a lot of very efficient radiowave squirt guns.

I was wrong about the cell phone and the heart monitors earlier it was a portable CD player

Other Technology-Related Proceedings Articles Explore Concerns for Patients

Two
other pieces in the March issue of Mayo Clinic Proceedings also address
whether technological devices interfere with patient care equipment.
Unlike the cellular phone study, the other reports detail technological
devices that caused patient care equipment to malfunction.

A
letter to the editor published in the journal details the first known
case of a portable CD player causing an abnormal electrocardiographic
(ECG) recording within a hospital setting. The recording returned to
normal when the CD player, which the patient was holding close to the
ECG lead, was turned off.

Technology also can threaten
implantable rhythm devices such as pacemakers and defibrillators
outside the hospital setting, according to a journal report. The report
outlines two cases of retail stores' anti-theft devices causing
people's heart devices to malfunction.

The anti-theft devices are
commonly placed near store exits and entrances, triggering an alarm if
customers leave with merchandise that was not purchased. In two
instances in Tennessee, customers with a pacemaker and an implantable
cardiac defibrillator experienced adverse reactions after nearing
anti-theft devices.






Posted by: chad at September 01, 2007 04:12 PM (WNcvq)

85

Pajama?


Imagine what it takes to NOT have you get knocked up.


"Bunk!" is sort of an in joke.  I guess you missed it, though you should have gotten it, in more ways than one.  *licks lips*


Posted by: Wickedpinto at September 01, 2007 04:52 PM (QTv8u)

86

BUNK!!! is a type of bed, pajama momma.  Dur.


It's easier to jump on the trampoline. I don't hit my head that way.


Imagine what it takes to NOT have you get knocked up.


I get rid of my husband?


Posted by: pajama momma at September 02, 2007 05:30 AM (Tbl5c)

87 I also suspect, many manufacturers are submitting "special" samples for
FCC cert that have been hand manufactured and shielded to pass.  When
the cert is issued, the mass production units drop the shielding as a
cost cutting measure.

--This is exactly what people do. Its also why I would suggest anyone doing business with China to have their testing done in the USA with samples pulled off production lines by American staff. Otherwise, its all handmade samples being sent to Chinese labs who will accept bribes.

Posted by: Aaron at September 02, 2007 06:16 AM (YOJ7/)

88 My cell phone puts out RFI that freaks out my cheap clock radio. My embroidery machine, which is about 20 years old has a Z80 based motherboard, puts out a pretty powerful RF field when it powers up. It would overwhelm a cordless phone if I was within 5 feet of the electronics cabinet on the machine and it easily interferes with the same cheap clock radio on the other side of the room.

I also happen to live in one of the worst RFI fields in the world. Located in suburban Detroit, the RFI around here is so bad that all of the US auto mfgs and most of the imports come to my neighborhood to test onboard electronics for RFI rejection on camouflaged  preproduction cars.  Most cheap FM radios will simply not work here and some pretty pricey audiophile gear also has problems. I've ended up using a 1960 vintage  The Fisher FM-100-S vacuum tube tuner, because most new tuners are pretty crappy in terms of RFI rejection and shielding. Within five miles are the main broadcast towers for 6 FM stations, one AM station, two VHF tv stations, and three UHF tv stations. In the house my ex now owns, people think they've been put on hold on the phone because of the music they hear.

Posted by: Bozoer Rebbe at September 02, 2007 08:24 AM (Eg53w)

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