Kearnstd
Elf Wizard
Premium
join:2002-01-22
Mullica Hill, NJ
| reply to MoviePhreak9
Re: Nice Scam by Cingular
the GPS thing i never understood because a handheld GPS and infact any civilan GPS can only pickup the signal. as far as i know only very highest clearence could send anything back to the GPS sats from a moble station.
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[65 Arcanist]Filan(High Elf) Zone: Broadband Reports |
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voyager6868
join:2003-01-29
Lynnwood, WA | reply to Albertcrombie
Dude, you must have a really crappy monitor and speakers. My phone sits next to my speakers & monitor all day long (I answer calls with a headset) and I've never heard any crackling and never see any screen disturbance. |
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koolman2
Premium
join:2002-10-01
Anchorage, AK
 ·GCI.net
| reply to KB2PSM
said by KB2PSM  :giga stands for 10 to the 9th power. In the above example, it refers to 1,2100,000,000 watts. He was quoting the movie, "Back to the Future".
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A bus station is where a bus stops. A train station is where a train stops. On my desk, I have a work station. |
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raythompsontn
join:2001-01-11
Oliver Springs, TN
| reply to alphapointe
said by alphapointe :"What the hell is a gigawatt?" Enough to crinkle your rectum by golly.
Perhaps I should have written it a jiga-watt and perhaps it would ring a bell if you were to go back to the future. |
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KB2PSM
join:2002-08-06
Long Beach, NY | reply to alphapointe
giga stands for 10 to the 9th power.
In the above example, it refers to 1,2100,000,000 watts. |
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alphapointe
Premium,MVM
join:2002-02-10
Columbia, MO
clubs: | reply to raythompsontn
"What the hell is a gigawatt?" |
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bart99gt
join:2001-03-24
Newnan, GA
| reply to Albertcrombie
Umm, maybe if it was sitting right next to the radio. Every kind of interference you described only has an effect if the phone is within a few inches of the device in question. Also the devices you mentioned are not designed (nor are they required) to shield themselves from such interference. Aircraft radios on the other hand have to be designed to reject any spurious interference from other RF transmitters in the area by using notch and bandpass filters that reject any out of band interference. Both the FCC and FAA have very tight regulations and testing that these radios and intercoms must pass before they will be approved for use in an airplane. In fact, there has been no documented case of a cell phone actually interfering with the radio or avionics in any airplane. They were banned over concerns of potential interference nearly 14 years ago, when most phones operated with a far higher power output than they do today.
I bring up handheld GPS devices only because many airlines have banned their use inside airliners for the same non-existant interference issue. If that were the case then there would be countless general aviation aircraft having regular avionics malfunctions from pilots using them. |
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Combat Chuck
Too Many Cannibals
Premium
join:2001-11-29
Erie, PA
| reply to Albertcrombie
So we're just lucky Al-Q hasn't noticed this huge threat.
Again, I remind you razor blades are banned (something that would relatively easy for anyone with a pair of shoes to defend against, might lose a passenger or 2), but we're allowing dangerous RF emitting equipment on the plane. Think about it.
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Beagles really should come in convienent 10 packs. |
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raythompsontn
join:2001-01-11
Oliver Springs, TN
| reply to Albertcrombie
said by Albertcrombie:
Sure, so whenever I turn my cell on and place a call next to my computer monitor (75Hz) and the screen becomes blured momentarily it is because of my girlfriend's hairdryer, right?
Oh and what about when i move my phone next to my speakers and I hear this weird intermittent noise ?? Your laptop is not even close to being shielded as well as the avionics in a typical aircraft. The interference is from low level harmonics and the circuit paths in your unshielded laptop are acting as a small antenna.
Aircraft electronics have to be highly shielded to protect against other system on the aircraft.
Aircraft transmission and receiving systems are also very, very selective in the frequencies that they allow to pass and odd harmonics are not on the list.
Besides, you 75HZ laptop screen is operating at a much higher frequency. The 75HZ is simply the refresh rate and is the number of times a second the screen is redrawn. Has nothing to do with the internal operating frequencies of the laptop.
Your statement about the laptop 75HZ, and your girlfriends hairdryer (motor with brushes that produces lots of harmonics from the slight sparking of the brushes) indicate that you know little about radio frequencies and how they work.
If an airplane can tolerate a lightning hit with more than a few watts of power (1.21 gigawatts according to Doc Brown), your cell phone is not going to be a problem.
The experts know and if there was even the slightest risk of compromising aviation electronics cell phones would not be allowed. |
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birke
@63.89.x.x | reply to Combat Chuck
yep, i think you're right. once again, the mighty dollars rules the day. |
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Albertcrombie
@nsc.com
|  reply to bart99gt
Sure, so whenever I turn my cell on and place a call next to my computer monitor (75Hz) and the screen becomes blured momentarily it is because of my girlfriend's hairdryer, right?
Oh and what about when i move my phone next to my speakers and I hear this weird intermittent noise ??
Come on, the cell phones might not interfer with the airwaves between the pilot's radio system and the ground station radio system but they are creating disturbance in the pilot radio system.
Now imagine hundreds of cell phones being used by passengers in the airplane, each trying to communicate "louder" than the other, increasing the watts of power of the radio signal, all creating this noise on the radio of this guy who has all those lives in his hands.
Please keep the cells banned on airplanes.
Oh and by the way a GPS handset will not create any interferences of any kind since it is only receiving the GPS signal and not sending anything back... |
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bart99gt
join:2001-03-24
Newnan, GA
| reply to AlbertCrombie
Aviation Nav and Comm frequencies are between 108 MHz and 137 MHz. Distance Measuring Equipment(DME)uses frequencies between 960 and 1215 MHz. There are also some non-directional beacons (NDB)located between 190-535 KHz, but they are being phased out in many areas and are more likely to receive interference from AM radio stations and lightning than a cell phone. I've used my cell phone countless times when flying in private aircraft (where there is no ban, it is up to the discretion of the pilot) and I have never seen a cell phone, GPS, laptop, etc., interfere with the radios in the aircraft. I doubt the FAA would even consider rescinding the ban if there was any possibility that a cell phone could really interfere with the navigation and communication equipment in an airliner.
These are fairly standardized frequency assignments worldwide so that aircraft from virtually any nation can communicate and use radionavigation beacons all around the world. I doubt that there are cellular frequencies anywhere in the world that overlap frequencies used in aviation. |
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AlbertCrombie
@nsc.com
| reply to Combat Chuck
No it is really because of the interferences. Whenever you use a GSM phone it creates interferences in the airplane radio system, so the pilot is not able to communicate properly with the ground station, which would be very dangerous especially while landing or taking off.
I remember one day we were on the ground already and the plane was in transit to the terminal and some people turned their cell on an the pilot made an angry announcement reminding people to shut it off.
for info your phone might not interfer, but GSM is not only usa frequencies...
GSM400 450.4 - 457.6 MHz paired with 460.4 - 467.6 MHz
or 478.8 - 486 MHz paired with 488.8 - 496 MHz
GSM850 824 - 849 MHz paired with 869 - 894 MHz
GSM900 880 - 915 MHz paired with 925 - 960 MHz
GSM1800 1710 - 1785 MHz paired with 1805 - 1880 MHz
GSM1900 1850 - 1910 MHz paired with 1930 - 1990 MHz |
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ossito16
join:2004-07-31
Whiting, IN | reply to Combat Chuck
Yeah, I never thought about that, point taken. |
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Combat Chuck
Too Many Cannibals
Premium
join:2001-11-29
Erie, PA
| reply to ossito16
said by ossito16 :I agree with you. I don't want to be on some plane and die cuz some clown needs to use cell phone. phone calls are useless in the air. make calls b4 and after flight. Properly shielded laptops you can rent at ticket desk or from stewardess giving you internet access. The interference issue is a ruse to deflect attention away from the real problem which is the issue of cell system not being able to cope with phones being in contact with potentially thousands of cells; and that from what I was told by a reputable source, one side effect is that the callers don't get billed.
Think about it, if electronic interference were really an issue electronics would be banned from all flights, as they could be used to bring down planes. You really think they'd be banning razors and not something that could screw with the avionics?
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Beagles really should come in convienent 10 packs. |
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ossito16
join:2004-07-31
Whiting, IN
·RCN CABLE
| reply to MoviePhreak9
I agree with you. I don't want to be on some plane and die cuz some clown needs to use cell phone. phone calls are useless in the air. make calls b4 and after flight. Properly shielded laptops you can rent at ticket desk or from stewardess giving you internet access. |
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MoviePhreak9
.
join:2002-07-17
India
| Yeah I agree, its a great way for Cingular to make money. However I do see that it could be a liability if some how a plane crashes (which is inevitable) and someone is talking on their cell phone (which is also inevitable; even though the cell phone might not be the cause of the plane crash).
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I'm Brown, I'm Hindu, and no I won't bomb your house and I don't have a frickin' gas station or qwicky mart...But my dad has a quiznos :P |
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