"Geoff Glave" wrote in message
news:HxHud.9448$eb3.8331@clgrps13...
Any explanation for this?

FM radio generally operates at longer range than AM radio,

Nonsense! AM radio stations can be heard for thousands of miles, FM for
'line of sight', which is usually less than a hundred miles.

however it's
limited to line-of-sight. However, when you're 40,000 feet up you can
"see" a lot of transmitters hence the FM signals.

Nonsense! The passenger is sitting in a Faraday Cage, a fuslage made of
alumninum. The FM wavelength is short enough to go thru the windows,
but mot the AM signals.


Cheers,
Geoff Glave
Vancouver, Canada

"Ian Jackson" wrote in
message ...
In message HxHud.9448$eb3.8331@clgrps13, Geoff Glave
writes
Any explanation for this?

FM radio generally operates at longer range than AM radio, however
it's
limited to line-of-sight. However, when you're 40,000 feet up you
can "see"
a lot of transmitters hence the FM signals.

Cheers,
Geoff Glave
Vancouver, Canada



The window holes are much too small to let the much longer wavelengths
of the 'AM' signals through. The body of the plane is a very effective
screen. The 'FM' signals can squeeze in, but it helps if you have a
window seat. I've also listened to SW in the middle of the Atlantic.

Flying from the UK to Florida, on the other side of the Atlantic the
first FM stations you hear are usually speaking French (from Quebec)
It's quite alarming!
Ian.
--

If you stretch a string on a globe from London to Florida, it will show
the 'great circle' route that's the shortest, and that should be your
plane's path, barring storme, hurricanes, etc. You'll see that it comes
really close to the eastern Canadian provinces.

"Richard Clark" wrote in message
...
On Sat, 11 Dec 2004 14:11:44 -0800, "Ed Price"
wrote:

You
are asking him to allow a potentially dangerous device to be operated
just
for your convenience and entertainment. Switch roles for just a
minute.

Hi Ed,

This would make sense (to switch roles) if the administration hadn't
trumped that call. Reports recently indicate that the FAA may soon
allow anyone, anytime, to make cell phone calls while in flight.

Anything goes for a price. The FDA has proven that it is no longer
the watchdog of medicine, and the FCC is the gateway for spectrum
bargains and marketplace sweeps.

With these acronyms, one may well wonder what the "F" stands for.

73's
Richard Clark, KB7QHC

If you make your own TRF receiver, with no LO, it won't interfere with
anything. In fact, you can then put an AM detector in it, and also
listen to the aircraft chatter.

Another way is to listen to stations at or below 97.3 MHz, which would
keep the LO at 108 MHz or below.

"Some Guy" wrote in message
...
What a load of horse ****.

You guys are acting as if the engines and flight control surfaces of
an aircraft are intimately tied to the plane's radio receiver, and the
slightest odd or out-of-place signal that it receives is enough to
send any plane into a tail spin.

No, the laws say that you can be arrested for breaking them, and one way
to break them is to use a FM radio while the aircraft is flying.

All this while the air travel industry is considering allowing
passengers to use their own cell phones WHILE THE PLANES ARE IN FLIGHT
by adding cell-phone relay stations to the planes and allowing any
such calls to be completed via satellite. So I guess the feeble
radiation by my FM radio (powered by 2 AAA batteries) is enough to
cause a plane to dive into the ocean, but the guy next to me putting
out 3 watts of near-microwave energy is totally safe.

You don't know what you're talking about. With the attitudes of the air
marshals nowadays, making airliners turn around and go back to their
departure point just because a passenger is unruly, there is a high
probability that one of them is flying along on your flight, and if he
sees an earphone hanging out of your ear, you might be that unruly
passenger they arrest at the departure point. Especially with your
nasty attitude!

What about my hand-held GPS unit? Any chance me using it (during all
phases of a flight, which I do routinely) will result in a one-way
ticket to kingdom come?

Geez, what a TWERP! You can't add two and two without jumping to
conclusions! A rational conversation with you is nearly impossible.

Getting back to the original question (poor to non-existant AM
reception), I understand the idea of aperature and long wavelenths of
AM radio and the size of airplane windows - but what about the effect
of ALL the windows on a plane? Don't they create a much larger
effective apperature when you consider all of them? And since the
plane isin't grounded, isin't the exterior shell of a plane
essentially transparent to all RF (ie it's just a re-radiator) because
it's not at ground potential?

You're even dumber than I had thought. Look up Faraday Shield.
Here, try this: http://www.physlink.com/Education/AskExperts/ae176.cfm
You don't have to worry about a ground for it to work. Duh.

"Watson A.Name - "Watt Sun, the Dark Remover"" wrote
in message ...

"Richard Clark" wrote in message
...
On Sat, 11 Dec 2004 14:11:44 -0800, "Ed Price"
wrote:

You
are asking him to allow a potentially dangerous device to be operated
just
for your convenience and entertainment. Switch roles for just a
minute.

Hi Ed,

This would make sense (to switch roles) if the administration hadn't
trumped that call. Reports recently indicate that the FAA may soon
allow anyone, anytime, to make cell phone calls while in flight.

Anything goes for a price. The FDA has proven that it is no longer
the watchdog of medicine, and the FCC is the gateway for spectrum
bargains and marketplace sweeps.

With these acronyms, one may well wonder what the "F" stands for.

73's
Richard Clark, KB7QHC

If you make your own TRF receiver, with no LO, it won't interfere with
anything. In fact, you can then put an AM detector in it, and also
listen to the aircraft chatter.

Another way is to listen to stations at or below 97.3 MHz, which would
keep the LO at 108 MHz or below.




Like maybe putting the LO at about 80 MHz, so that the 3rd harmonic of the
LO drops into the UHF navcom band?

Ed
wb6wsn

"Watson A.Name - "Watt Sun, the Dark Remover"" wrote
in message ...

"Some Guy" wrote in message
...
What a load of horse ****.

You guys are acting as if the engines and flight control surfaces of
an aircraft are intimately tied to the plane's radio receiver, and the
slightest odd or out-of-place signal that it receives is enough to
send any plane into a tail spin.

No, the laws say that you can be arrested for breaking them, and one way
to break them is to use a FM radio while the aircraft is flying.

All this while the air travel industry is considering allowing
passengers to use their own cell phones WHILE THE PLANES ARE IN FLIGHT
by adding cell-phone relay stations to the planes and allowing any
such calls to be completed via satellite. So I guess the feeble
radiation by my FM radio (powered by 2 AAA batteries) is enough to
cause a plane to dive into the ocean, but the guy next to me putting
out 3 watts of near-microwave energy is totally safe.

You don't know what you're talking about. With the attitudes of the air
marshals nowadays, making airliners turn around and go back to their
departure point just because a passenger is unruly, there is a high
probability that one of them is flying along on your flight, and if he
sees an earphone hanging out of your ear, you might be that unruly
passenger they arrest at the departure point. Especially with your
nasty attitude!

What about my hand-held GPS unit? Any chance me using it (during all
phases of a flight, which I do routinely) will result in a one-way
ticket to kingdom come?

Geez, what a TWERP! You can't add two and two without jumping to
conclusions! A rational conversation with you is nearly impossible.

Getting back to the original question (poor to non-existant AM
reception), I understand the idea of aperature and long wavelenths of
AM radio and the size of airplane windows - but what about the effect
of ALL the windows on a plane? Don't they create a much larger
effective apperature when you consider all of them? And since the
plane isin't grounded, isin't the exterior shell of a plane
essentially transparent to all RF (ie it's just a re-radiator) because
it's not at ground potential?

You're even dumber than I had thought. Look up Faraday Shield.
Here, try this: http://www.physlink.com/Education/AskExperts/ae176.cfm
You don't have to worry about a ground for it to work. Duh.


He's not dumber than "I" thought!

Ed
wb6wsn

Ed Price wrote:

"Watson A.Name - "Watt Sun, the Dark Remover"" wrote
in message ...

"Richard Clark" wrote in message
...
On Sat, 11 Dec 2004 14:11:44 -0800, "Ed Price"
wrote:

You
are asking him to allow a potentially dangerous device to be operated
just
for your convenience and entertainment. Switch roles for just a
minute.

Hi Ed,

This would make sense (to switch roles) if the administration hadn't
trumped that call. Reports recently indicate that the FAA may soon
allow anyone, anytime, to make cell phone calls while in flight.

Anything goes for a price. The FDA has proven that it is no longer
the watchdog of medicine, and the FCC is the gateway for spectrum
bargains and marketplace sweeps.

With these acronyms, one may well wonder what the "F" stands for.

73's
Richard Clark, KB7QHC

If you make your own TRF receiver, with no LO, it won't interfere with
anything. In fact, you can then put an AM detector in it, and also
listen to the aircraft chatter.

Another way is to listen to stations at or below 97.3 MHz, which would
keep the LO at 108 MHz or below.




Like maybe putting the LO at about 80 MHz, so that the 3rd harmonic of the
LO drops into the UHF navcom band?

Ed
wb6wsn

It is official; i just read in one of my electronigs mags i get that
the FAA indeed has ruled that airlines can allow use of computers over
the net when flying.
But it is up to each given airline to modify their own giudelines (as
they see fit).

Ed Price wrote:

"Watson A.Name - "Watt Sun, the Dark Remover"" wrote
in message ...

"Some Guy" wrote in message
...
What a load of horse ****.

You guys are acting as if the engines and flight control surfaces of
an aircraft are intimately tied to the plane's radio receiver, and the
slightest odd or out-of-place signal that it receives is enough to
send any plane into a tail spin.

No, the laws say that you can be arrested for breaking them, and one way
to break them is to use a FM radio while the aircraft is flying.

All this while the air travel industry is considering allowing
passengers to use their own cell phones WHILE THE PLANES ARE IN FLIGHT
by adding cell-phone relay stations to the planes and allowing any
such calls to be completed via satellite. So I guess the feeble
radiation by my FM radio (powered by 2 AAA batteries) is enough to
cause a plane to dive into the ocean, but the guy next to me putting
out 3 watts of near-microwave energy is totally safe.

You don't know what you're talking about. With the attitudes of the air
marshals nowadays, making airliners turn around and go back to their
departure point just because a passenger is unruly, there is a high
probability that one of them is flying along on your flight, and if he
sees an earphone hanging out of your ear, you might be that unruly
passenger they arrest at the departure point. Especially with your
nasty attitude!

What about my hand-held GPS unit? Any chance me using it (during all
phases of a flight, which I do routinely) will result in a one-way
ticket to kingdom come?

Geez, what a TWERP! You can't add two and two without jumping to
conclusions! A rational conversation with you is nearly impossible.

Getting back to the original question (poor to non-existant AM
reception), I understand the idea of aperature and long wavelenths of
AM radio and the size of airplane windows - but what about the effect
of ALL the windows on a plane? Don't they create a much larger
effective apperature when you consider all of them? And since the
plane isin't grounded, isin't the exterior shell of a plane
essentially transparent to all RF (ie it's just a re-radiator) because
it's not at ground potential?

You're even dumber than I had thought. Look up Faraday Shield.
Here, try this: http://www.physlink.com/Education/AskExperts/ae176.cfm
You don't have to worry about a ground for it to work. Duh.


He's not dumber than "I" thought!

Ed
wb6wsn

"Faraday shield" to some degree is a myth.
I have seen radars inside quonset huts track a *bird* flying a few
miles away (thru the metal wall)!

"Robert Baer" wrote in message
...
Ed Price wrote:

"Watson A.Name - "Watt Sun, the Dark Remover""
wrote
in message ...

"Some Guy" wrote in message
...
What a load of horse ****.

You guys are acting as if the engines and flight control surfaces of
an aircraft are intimately tied to the plane's radio receiver, and the
slightest odd or out-of-place signal that it receives is enough to
send any plane into a tail spin.

No, the laws say that you can be arrested for breaking them, and one
way
to break them is to use a FM radio while the aircraft is flying.

All this while the air travel industry is considering allowing
passengers to use their own cell phones WHILE THE PLANES ARE IN FLIGHT
by adding cell-phone relay stations to the planes and allowing any
such calls to be completed via satellite. So I guess the feeble
radiation by my FM radio (powered by 2 AAA batteries) is enough to
cause a plane to dive into the ocean, but the guy next to me putting
out 3 watts of near-microwave energy is totally safe.

You don't know what you're talking about. With the attitudes of the
air
marshals nowadays, making airliners turn around and go back to their
departure point just because a passenger is unruly, there is a high
probability that one of them is flying along on your flight, and if he
sees an earphone hanging out of your ear, you might be that unruly
passenger they arrest at the departure point. Especially with your
nasty attitude!

What about my hand-held GPS unit? Any chance me using it (during all
phases of a flight, which I do routinely) will result in a one-way
ticket to kingdom come?

Geez, what a TWERP! You can't add two and two without jumping to
conclusions! A rational conversation with you is nearly impossible.

Getting back to the original question (poor to non-existant AM
reception), I understand the idea of aperature and long wavelenths of
AM radio and the size of airplane windows - but what about the effect
of ALL the windows on a plane? Don't they create a much larger
effective apperature when you consider all of them? And since the
plane isin't grounded, isin't the exterior shell of a plane
essentially transparent to all RF (ie it's just a re-radiator) because
it's not at ground potential?

You're even dumber than I had thought. Look up Faraday Shield.
Here, try this: http://www.physlink.com/Education/AskExperts/ae176.cfm
You don't have to worry about a ground for it to work. Duh.


He's not dumber than "I" thought!

Ed
wb6wsn

"Faraday shield" to some degree is a myth.
I have seen radars inside quonset huts track a *bird* flying a few
miles away (thru the metal wall)!

You must have some strange buddies. Who in the world would set up a radar
within a metal hut? And even if they did, who would think it's a good idea
to stay inside with it if it were on?

There's nothing mythical about the Faraday shield; it works really well, so
long as there are no discontinuities (apertures) and sufficient thickness
and conductivity. Under real-world conditions, steel works pretty good, and
any thickness sufficient to support itself will yield great shielding
effectiveness. So the only real performance variable left is the holes in
the conductive surface. How many, maximum dimension, proximity of radiating
source to the shield, etc.

While I would expect a Quonset hut to really mess up the accuracy of a
radar, it likely wouldn't be a good shield, as the floor isn't metal, I
don't think the ends are metal, and the various skin panels are rather
poorly RF bonded.

Ed
wb6wsn

"Robert Baer" wrote in message
...
Ed Price wrote:

"Watson A.Name - "Watt Sun, the Dark Remover""
wrote
in message ...

"Some Guy" wrote in message
...
What a load of horse ****.

You guys are acting as if the engines and flight control surfaces
of
an aircraft are intimately tied to the plane's radio receiver,
and the
slightest odd or out-of-place signal that it receives is enough
to
send any plane into a tail spin.

No, the laws say that you can be arrested for breaking them, and
one way
to break them is to use a FM radio while the aircraft is flying.

All this while the air travel industry is considering allowing
passengers to use their own cell phones WHILE THE PLANES ARE IN
FLIGHT
by adding cell-phone relay stations to the planes and allowing
any
such calls to be completed via satellite. So I guess the feeble
radiation by my FM radio (powered by 2 AAA batteries) is enough
to
cause a plane to dive into the ocean, but the guy next to me
putting
out 3 watts of near-microwave energy is totally safe.

You don't know what you're talking about. With the attitudes of
the air
marshals nowadays, making airliners turn around and go back to
their
departure point just because a passenger is unruly, there is a
high
probability that one of them is flying along on your flight, and
if he
sees an earphone hanging out of your ear, you might be that unruly
passenger they arrest at the departure point. Especially with
your
nasty attitude!

What about my hand-held GPS unit? Any chance me using it (during
all
phases of a flight, which I do routinely) will result in a
one-way
ticket to kingdom come?

Geez, what a TWERP! You can't add two and two without jumping to
conclusions! A rational conversation with you is nearly
impossible.

Getting back to the original question (poor to non-existant AM
reception), I understand the idea of aperature and long
wavelenths of
AM radio and the size of airplane windows - but what about the
effect
of ALL the windows on a plane? Don't they create a much larger
effective apperature when you consider all of them? And since
the
plane isin't grounded, isin't the exterior shell of a plane
essentially transparent to all RF (ie it's just a re-radiator)
because
it's not at ground potential?

You're even dumber than I had thought. Look up Faraday Shield.
Here, try this:
http://www.physlink.com/Education/AskExperts/ae176.cfm
You don't have to worry about a ground for it to work. Duh.


He's not dumber than "I" thought!

Ed
wb6wsn

"Faraday shield" to some degree is a myth.

You use weasel words like 'to some degree' to avoid talking about the
truth. Radio waves don't go thru a sheet of metal.

I have seen radars inside quonset huts track a *bird* flying a few
miles away (thru the metal wall)!

No, not thru a metal wall. I saw the radar go thru the wooden walls of
the bldg when I was in radar repair school in the army. But that was
wood. Your so-called metal quonset hut was probably wood or fiberglass.

If you saw anything, it was probably your own reflection off the metal
walls, IF it didn't fry you like a porkchop in a microwave oven!