Speed of waves
 

"This finding had practical applications for telegraph communications. For
example, Heaviside actually solved one of the biggest problems affecting
long distance telegraph and telephone communication in 1887 -distortion. It
was known that different frequencies travel with different speeds on a long
cable. For example, the low bass frequencies in a voice signal travel faster
than the high treble frequencies. When the cable is long enough, the
frequencies smear, and both voice and telegraph signals become garbled
noise. Heaviside used his equations to show that if inductances (i.e., a
small coil of wire) were added along the length of the cable, the distortion
could be reduced." From:
http://www.ieeeghn.org/wiki/index.php/Oliver_Heaviside

" It was known that different frequencies travel with different speeds on a
long cable".

Is the same in air and space?
S*

Speed of waves
 

On Thu, 24 Mar 2011 10:53:09 +0100, Szczepan Bialek rearranged some
electrons to say:


" It was known that different frequencies travel with different speeds
on a long cable".

Is the same in air and space?
S*

No, how many people have to tell you that?

Speed of waves
 

On 24 mar, 10:53, "Szczepan Bialek" wrote:
"This finding had practical applications for telegraph communications. For
example, Heaviside actually solved one of the biggest problems affecting
long distance telegraph and telephone communication in 1887 -distortion. It
was known that different frequencies travel with different speeds on a long
cable. For example, the low bass frequencies in a voice signal travel faster
than the high treble frequencies. When the cable is long enough, the
frequencies smear, and both voice and telegraph signals become garbled
noise. Heaviside used his equations to show that if inductances (i.e., a
small coil of wire) were added along the length of the cable, the distortion
could be reduced." From:http://www.ieeeghn.org/wiki/index.php/Oliver_Heaviside

" It was known that different frequencies travel with different speeds on a
long cable".

Is the same in air and space?
S*

Hello Szczepan,

Search for the effective permittivity of media with free electrons
(plasma). You will see that the effective permittivity changes with
frequency, hence the phase velocity. Don't look strange to find
apparent permittivities below the value for vacuum.

Just ignore DC magnetic field as this complicates that math
significantly.


Wim
PA3DJS
www.tetech.nl
without abc, PM will reach me.

Speed of waves
 

"Wimpie" napisal w wiadomosci
...
On 24 mar, 10:53, "Szczepan Bialek" wrote:
"This finding had practical applications for telegraph communications.
For
example, Heaviside actually solved one of the biggest problems affecting
long distance telegraph and telephone communication in 1887 -distortion.
It
was known that different frequencies travel with different speeds on a
long
cable. For example, the low bass frequencies in a voice signal travel
faster
than the high treble frequencies. When the cable is long enough, the
frequencies smear, and both voice and telegraph signals become garbled
noise. Heaviside used his equations to show that if inductances (i.e., a
small coil of wire) were added along the length of the cable, the
distortion
could be reduced."
From:http://www.ieeeghn.org/wiki/index.php/Oliver_Heaviside

" It was known that different frequencies travel with different speeds on
a
long cable".

Is the same in air and space?
S*

Hello Szczepan,

Search for the effective permittivity of media with free electrons
(plasma). You will see that the effective permittivity changes with
frequency, hence the phase velocity. Don't look strange to find
apparent permittivities below the value for vacuum.

Just ignore DC magnetic field as this complicates that math
significantly.

Hello Wim,

So you confirm that in plasma is the same as in metal.

But what with the space. The AM should be better than FM to communicate with
the Mars.
Is/were FM used for long distances?

Were done the proper experiments in the early years of radio?
S*

Speed of waves
 

"david" napisa³ w wiadomo¶ci
...
On Thu, 24 Mar 2011 10:53:09 +0100, Szczepan Bialek rearranged some
electrons to say:


" It was known that different frequencies travel with different speeds
on a long cable".

Is the same in air and space?
S*

No, how many people have to tell you that?

And what they tell:
"Because of the low signal-to-noise ratio, as with amateur-radio practice,
EME signals can generally only be detected using narrow-band receiving
systems. This means that the only aspect of the TV signal that could be
detected is the field scan modulation (AM vision carrier). FM broadcast
signals also feature wide frequency modulation, hence EME reception is
generally not possible. There are no published records of VHF/UHF EME
amateur radio contacts using FM." From:
http://en.wikipedia.org/wiki/TV_and_FM_DX

Could you explain it?

S*

Speed of waves
 

On 24 mar, 18:42, "Szczepan Bialek" wrote:
*"Wimpie" napisal w ...



On 24 mar, 10:53, "Szczepan Bialek" wrote:
"This finding had practical applications for telegraph communications.
For
example, Heaviside actually solved one of the biggest problems affecting
long distance telegraph and telephone communication in 1887 -distortion.

Speed of waves
 

Szczepan Bialek wrote:

"david" napisa? w wiadomo?ci
...
On Thu, 24 Mar 2011 10:53:09 +0100, Szczepan Bialek rearranged some
electrons to say:


" It was known that different frequencies travel with different speeds
on a long cable".

Is the same in air and space?
S*

No, how many people have to tell you that?

And what they tell:
"Because of the low signal-to-noise ratio, as with amateur-radio practice,
EME signals can generally only be detected using narrow-band receiving
systems. This means that the only aspect of the TV signal that could be
detected is the field scan modulation (AM vision carrier). FM broadcast
signals also feature wide frequency modulation, hence EME reception is
generally not possible. There are no published records of VHF/UHF EME
amateur radio contacts using FM." From:
http://en.wikipedia.org/wiki/TV_and_FM_DX

Could you explain it?

Explain what?

You quote has absolutely nothing to do with the speed of propagation, you
babbling moron.


--
Jim Pennino

Remove .spam.sux to reply.

Speed of waves
 

On 3/24/2011 1:06 PM, Wimpie wrote:
On 24 mar, 18:42, "Szczepan wrote:
napisal w ...

But what with the space. The AM should be better than FM to communicate with
the Mars.
Is/were FM used for long distances?

As power is limiting factor, a modulation scheme with coherent
detection and digital decoding will give best performance (best Eb/N0
ratio for certain BER) I think. So it is not just a question of AM or
FM/PM, but more how it is processed at the receiver. Processing power
changed over time, so theoretically the best method may not be used
because of technical limitations.

Were done the proper experiments in the early years of radio?
S*

Best regards,

Wim
PA3DJS
www.tetech.nl


There's a non-zero chance you went beyond his knowledge base. :) (no ;
needed)

tom
K0TAR

Speed of waves
 

Uzytkownik "Wimpie" napisal w wiadomosci
...
On 24 mar, 18:42, "Szczepan Bialek" wrote:
"Wimpie" napisal w
...



On 24 mar, 10:53, "Szczepan Bialek" wrote:
"This finding had practical applications for telegraph communications.
For
example, Heaviside actually solved one of the biggest problems
affecting
long distance telegraph and telephone communication in
1887 -distortion.
It
was known that different frequencies travel with different speeds on a
long
cable. For example, the low bass frequencies in a voice signal travel
faster
than the high treble frequencies. When the cable is long enough, the
frequencies smear, and both voice and telegraph signals become garbled
noise. Heaviside used his equations to show that if inductances (i.e.,
a
small coil of wire) were added along the length of the cable, the
distortion
could be reduced."
From:http://www.ieeeghn.org/wiki/index.php/Oliver_Heaviside

" It was known that different frequencies travel with different speeds
on
a
long cable".

Is the same in air and space?
S*

Hello Szczepan,

Search for the effective permittivity of media with free electrons
(plasma). You will see that the effective permittivity changes with
frequency, hence the phase velocity. Don't look strange to find
apparent permittivities below the value for vacuum.

Just ignore DC magnetic field as this complicates that math
significantly.

Hello Wim,

So you confirm that in plasma is the same as in metal.

No


But what with the space. The AM should be better than FM to communicate
with
the Mars.
Is/were FM used for long distances?

As power is limiting factor, a modulation scheme with coherent
detection and digital decoding will give best performance (best Eb/N0
ratio for certain BER) I think. So it is not just a question of AM or
FM/PM, but more how it is processed at the receiver. Processing power
changed over time, so theoretically the best method may not be used
because of technical limitations.

Were done the proper experiments in the early years of radio?
S*

Best regards,

Wim

I am simple asking if radio people have trouble with the fact that the speed
of waves are frequeny dependent.
I am interesting with the real radio waves in the real media. Here is an
example Pulsars are spinning neutron stars that emit pulses at very regular
intervals ranging from milliseconds to seconds. Astronomers believe that the
pulses are emitted simultaneously over a wide range of frequencies. However,
as observed on Earth, the components of each pulse emitted at higher radio
frequencies arrive before those emitted at lower frequencies. This
dispersion occurs because of the ionised component of the interstellar
medium, which makes the group velocity frequency dependent

S

Speed of waves
 

On 25 mar, 10:17, "Szczepan Bialek" wrote:
Uzytkownik "Wimpie" napisal w ...
On 24 mar, 18:42, "Szczepan Bialek" wrote:



"Wimpie" napisal w
...

On 24 mar, 10:53, "Szczepan Bialek" wrote:
"This finding had practical applications for telegraph communications.
For
example, Heaviside actually solved one of the biggest problems
affecting
long distance telegraph and telephone communication in
1887 -distortion.
It
was known that different frequencies travel with different speeds on a
long
cable. For example, the low bass frequencies in a voice signal travel
faster
than the high treble frequencies. When the cable is long enough, the
frequencies smear, and both voice and telegraph signals become garbled
noise. Heaviside used his equations to show that if inductances (i.e..,
a
small coil of wire) were added along the length of the cable, the
distortion
could be reduced."
From:http://www.ieeeghn.org/wiki/index.php/Oliver_Heaviside

" It was known that different frequencies travel with different speeds
on
a
long cable".

Is the same in air and space?
S*

Hello Szczepan,

Search for the effective permittivity of media with free electrons
(plasma). You will see that the effective permittivity changes with
frequency, hence the phase velocity. Don't look strange to find
apparent permittivities below the value for vacuum.

Just ignore DC magnetic field as this complicates that math
significantly.

Hello Wim,

So you confirm that in plasma is the same as in metal.

No



But what with the space. The AM should be better than FM to communicate
with
the Mars.
Is/were FM used for long distances?

As power is limiting factor, a modulation scheme with coherent
detection and digital decoding will give best performance (best Eb/N0
ratio for certain BER) I think. So it is not just a question of AM or
FM/PM, but more how it is processed at the receiver. *Processing power
changed over time, so theoretically the best method may not be used
because of technical limitations.



Were done the proper experiments in the early years of radio?
S*

Best regards,

Wim

I am simple asking if radio people have trouble with the fact that the speed
of waves are frequeny dependent.
I am interesting with the real radio waves in the real media. Here is an
example Pulsars are spinning neutron stars that emit pulses at very regular
intervals ranging from milliseconds to seconds. Astronomers believe that the
pulses are emitted simultaneously over a wide range of frequencies. However,
as observed on Earth, the components of each pulse emitted at higher radio
frequencies arrive before those emitted at lower frequencies. This
dispersion occurs because of the ionised component of the interstellar
medium, which makes the group velocity frequency dependent

S

Try to find document "Descanso4--Voyager_new.pdf" (very likely the
first result in google). This describes the Voyager communication
system. It is now more the 10 light hours from us (as far as I
know).

As far as I know, they don't equalize to correct for in band
dispersion (due to wave propagation). Maybe other people have better
info on this.

Best regards,

Wim
PA3DJS
www.tetech.nl

Speed of waves
 

"Wimpie" napisal w wiadomosci
...
On 25 mar, 10:17, "Szczepan Bialek" wrote:

I am simple asking if radio people have trouble with the fact that the
speed
of waves are frequeny dependent.
I am interesting with the real radio waves in the real media. Here is an
example: "Pulsars are spinning neutron stars that emit pulses at very
regular
intervals ranging from milliseconds to seconds. Astronomers believe that
the
pulses are emitted simultaneously over a wide range of frequencies.
However,
as observed on Earth, the components of each pulse emitted at higher radio
frequencies arrive before those emitted at lower frequencies. This
dispersion occurs because of the ionised component of the interstellar
medium, which makes the group velocity frequency dependent".

S

Try to find document "Descanso4--Voyager_new.pdf" (very likely the
first result in google). This describes the Voyager communication
system. It is now more the 10 light hours from us (as far as I
know).

As far as I know, they don't equalize to correct for in band
dispersion (due to wave propagation). Maybe other people have better
info on this.

They used the "Ultrastable oscillator".
They measure the ions and electrons density in the interstellar medium. So
the band dispersion is obvious and the only remedy is the "Ultrastable
oscillator".

So AM and FM are quite opposite. It seems to me that FM is not the best for
the long distances.

It seems to me that here is a confirmation of that: ""Because of the low
signal-to-noise ratio, as with amateur-radio practice,
EME signals can generally only be detected using narrow-band receiving
systems. This means that the only aspect of the TV signal that could be
detected is the field scan modulation (AM vision carrier). FM broadcast
signals also feature wide frequency modulation, hence EME reception is
generally not possible. There are no published records of VHF/UHF EME
amateur radio contacts using FM." From:
http://en.wikipedia.org/wiki/TV_and_FM_DX

I do not understand this but guess.

Best regards,

S*

Speed of waves
 

Szczepan Bialek wrote:

I am simple asking if radio people have trouble with the fact that the speed
of waves are frequeny dependent.

No, they are not because the speed of electromagnetic waves is NOT frequeny
dependent, the speed is media dependent, you babbling, ignorant, trolling,
moron.



--
Jim Pennino

Remove .spam.sux to reply.

Speed of waves
 

On Mar 24, 10:42*am, "Szczepan Bialek" wrote:
*"Wimpie" napisal w ...



On 24 mar, 10:53, "Szczepan Bialek" wrote:
"This finding had practical applications for telegraph communications.
For
example, Heaviside actually solved one of the biggest problems affecting
long distance telegraph and telephone communication in 1887 -distortion.

Speed of waves
 

On Mar 25, 5:54*am, Wimpie wrote:
On 25 mar, 10:17, "Szczepan Bialek" wrote:



Uzytkownik "Wimpie" napisal w ...
On 24 mar, 18:42, "Szczepan Bialek" wrote:

"Wimpie" napisal w
...

On 24 mar, 10:53, "Szczepan Bialek" wrote:
"This finding had practical applications for telegraph communications.
For
example, Heaviside actually solved one of the biggest problems
affecting
long distance telegraph and telephone communication in
1887 -distortion.
It
was known that different frequencies travel with different speeds on a
long
cable. For example, the low bass frequencies in a voice signal travel
faster
than the high treble frequencies. When the cable is long enough, the
frequencies smear, and both voice and telegraph signals become garbled
noise. Heaviside used his equations to show that if inductances (i..e.,
a
small coil of wire) were added along the length of the cable, the
distortion
could be reduced."
From:http://www.ieeeghn.org/wiki/index.php/Oliver_Heaviside

" It was known that different frequencies travel with different speeds
on
a
long cable".

Is the same in air and space?
S*

Hello Szczepan,

Search for the effective permittivity of media with free electrons
(plasma). You will see that the effective permittivity changes with
frequency, hence the phase velocity. Don't look strange to find
apparent permittivities below the value for vacuum.

Just ignore DC magnetic field as this complicates that math
significantly.

Hello Wim,

So you confirm that in plasma is the same as in metal.

No

But what with the space. The AM should be better than FM to communicate
with
the Mars.
Is/were FM used for long distances?

As power is limiting factor, a modulation scheme with coherent
detection and digital decoding will give best performance (best Eb/N0
ratio for certain BER) I think. So it is not just a question of AM or
FM/PM, but more how it is processed at the receiver. *Processing power
changed over time, so theoretically the best method may not be used
because of technical limitations.

Were done the proper experiments in the early years of radio?
S*

Best regards,

Wim

I am simple asking if radio people have trouble with the fact that the speed
of waves are frequeny dependent.
I am interesting with the real radio waves in the real media. Here is an
example Pulsars are spinning neutron stars that emit pulses at very regular
intervals ranging from milliseconds to seconds. Astronomers believe that the
pulses are emitted simultaneously over a wide range of frequencies. However,
as observed on Earth, the components of each pulse emitted at higher radio
frequencies arrive before those emitted at lower frequencies. This
dispersion occurs because of the ionised component of the interstellar
medium, which makes the group velocity frequency dependent

S

Try to find document "Descanso4--Voyager_new.pdf" (very likely the
first result in google). This describes the Voyager communication
system. It is now more the 10 light hours from us (as far as I
know).

The DESCANSO web site (http://descanso.jpl.nasa.gov/) has a variety of
reports and books available for online/download/free use that discuss
a lot of this stuff. Pretty much all the missions JPL has done in the
past few decades have a "design and performance" report out there that
describes the radio system and how it works. The monograph series has
a bunch of books on some general aspect (like large antennas or
autonomous radios).

the IPN progress reports (which has had various names over the years)
is more a peer reviewed journal of record for various work in space
communication, and all of it is freely downloadable, too.


As far as I know, they don't equalize to correct for in band
dispersion (due to wave propagation). Maybe other people have better
info on this.


No compensation is made for dispersion.. the bandwidth of the signal
is so narrow compared to the carrier frequency that dispersion in
propagation isn't a factor. The bumps in the group delay
characteristics of the radio components are orders of magnitude
greater. To minimize that, we tend to use designs that keep the
signal in the nominal center of the IF passband.

Where dispersion becomes interesting (and is actually measured) is
when comparing signals at two separated frequencies, e.g. 8.4 GHz and
32 GHz. Or, for a closer to earth example, L1 & L2 for GPS (separated
by a couple hundred MHz at 1500 MHz) allow for compensation for
ionospheric delays.

Speed of waves
 

On 25 mar, 15:52, "Szczepan Bialek" wrote:
*"Wimpie" napisal w ...
On 25 mar, 10:17, "Szczepan Bialek" wrote:





I am simple asking if radio people have trouble with the fact that the
speed
of waves are frequeny dependent.
I am interesting with the real radio waves in the real media. Here is an
example: "Pulsars are spinning neutron stars that emit pulses at very
regular
intervals ranging from milliseconds to seconds. Astronomers believe that
the
pulses are emitted simultaneously over a wide range of frequencies.
However,
as observed on Earth, the components of each pulse emitted at higher radio
frequencies arrive before those emitted at lower frequencies. This
dispersion occurs because of the ionised component of the interstellar
medium, which makes the group velocity frequency dependent".

S
Try to find document "Descanso4--Voyager_new.pdf" (very likely the

first result in google). This describes the Voyager communication
system. It is now more the 10 light hours from us (as far as I
know).

As far as I know, they don't equalize to correct for in band

dispersion (due to wave propagation). Maybe other people have better
info on this.

They used the "Ultrastable oscillator".
They measure the ions and electrons density in the interstellar medium. So
the band dispersion is obvious and the only remedy is the "Ultrastable
oscillator".

Sorry, I don't see the link between "ultrastable oscillator" and
dispersion. Good oscillators in both transmitting and receiving
equipment are required to get the lowest possible Eb/No for your
digital modulation scheme.


So AM and FM are quite opposite. *It seems to me that FM is not the best for
the long distances.

It seems to me that here is a confirmation of that: ""Because of the low
signal-to-noise ratio, as with amateur-radio practice,
EME signals can generally only be detected using narrow-band receiving
systems. This means that the only aspect of the TV signal that could be
detected is the field scan modulation (AM vision carrier). FM broadcast
signals also feature wide frequency modulation, hence EME reception is
generally not possible. There are no published records of VHF/UHF EME
amateur radio contacts using FM." From:http://en.wikipedia.org/wiki/TV_and_FM_DX

I do not understand this but guess.


Low bit rates, result in low required power, so it is true that with
the advent of low bitrate digital schemes, EME is within the reach of
more radio amateurs. As these modes use narrow bandwidth, dispersion
effects are negligible when looking to the demodulation of the
received signal (as far as I know). Even amateurs using satellite
communication with analog voice, don't have to modify their
demodulators.

Wim
PA3DJS

Speed of waves
 

On Mar 25, 7:52*am, "Szczepan Bialek" wrote:
*"Wimpie" napisal w ...
On 25 mar, 10:17, "Szczepan Bialek" wrote:





I am simple asking if radio people have trouble with the fact that the
speed
of waves are frequeny dependent.
I am interesting with the real radio waves in the real media. Here is an
example: "Pulsars are spinning neutron stars that emit pulses at very
regular
intervals ranging from milliseconds to seconds. Astronomers believe that
the
pulses are emitted simultaneously over a wide range of frequencies.
However,
as observed on Earth, the components of each pulse emitted at higher radio
frequencies arrive before those emitted at lower frequencies. This
dispersion occurs because of the ionised component of the interstellar
medium, which makes the group velocity frequency dependent".

S
Try to find document "Descanso4--Voyager_new.pdf" (very likely the

first result in google). This describes the Voyager communication
system. It is now more the 10 light hours from us (as far as I
know).

As far as I know, they don't equalize to correct for in band

dispersion (due to wave propagation). Maybe other people have better
info on this.

They used the "Ultrastable oscillator".
They measure the ions and electrons density in the interstellar medium. So
the band dispersion is obvious and the only remedy is the "Ultrastable
oscillator".

The USO has nothing to do with the dispersion. It's just something
that lets you make the measurement, because you can integrate over
100s of seconds, and know that the signal being transmitted didn't
change (much) during that time, so any changes are due to the
propagation.


So AM and FM are quite opposite. *It seems to me that FM is not the best for
the long distances.

It seems to me that here is a confirmation of that: ""Because of the low
signal-to-noise ratio, as with amateur-radio practice,
EME signals can generally only be detected using narrow-band receiving
systems. This means that the only aspect of the TV signal that could be
detected is the field scan modulation (AM vision carrier). FM broadcast
signals also feature wide frequency modulation, hence EME reception is
generally not possible. There are no published records of VHF/UHF EME
amateur radio contacts using FM." From:http://en.wikipedia.org/wiki/TV_and_FM_DX


I don't know that I'd use a wikipedia article as my primary reference
on this particular topic.

The reason hams don't do EME FM or EME TV is more a matter of link
budgets than propagation characteristics. amateurs are limited in the
maximum output power (e.g. 1500W PEP in the U.S.), and particularly if
they're using amateur antennas (no 300m dish at Arecibo), you don't
have enough radiated power density to send a wideband signal and have
it arrive back at earth with decent SNR. So, hams use narrow band
transmissions and narrow band receivers (so that they get the minimum
noise power in the detection bandwidth). (also, there's a cultural
thing.. the hams that are interested in TV aren't the same hams
interested in moonbounce, so there's not necessarily and motivation to
even try what would be a fairly difficult and expensive stunt)

If you're not limited by amateur budgets or regulatory power limits,
there's no reason you couldn't send FM or TV to the moon and back.
Apollo used FM in their Unified S-band system (granted, one way from
the moon, not a moonbounce). I haven't run the numbers, but maybe if
you had a big enough transmitter, and used something like Arecibo, you
could do moonbounce tv.

We send several MHz bandwidth back from Mars with a 100W transmitter,
a 3 meter dish, and receive it with a 34 meter dish on earth at
greater than 0dB SNR.

A big advantage of AM is that it has simple and cheap transmitters (a
modulated amplifier) and receivers (a diode). If you're spending
billions of dollars to send a probe to Mars, saving (relatively) small
amounts on the radio isn't worth it, especially if you have to spend
large amounts more on solar panels to get the additional DC power
needed.

That said, for short range links in space, FM, FSK, and AM are
considered as viable alternatives, especially where you are looking
for very small, very low mass. The Muses CN rover (which was about
the size of a pack of cards and was going to drive around an
asteroid's surface) was proposed to use a FSK data link, as I recall.
AM for astronaut backup voice comm is also a possibility.

Speed of waves
 

napisa³ w wiadomo¶ci
...
Szczepan Bialek wrote:

I am simple asking if radio people have trouble with the fact that the
speed
of waves are frequency dependent.

No, they are not because the speed of electromagnetic waves is NOT
frequency
dependent, the speed is media dependent,

"In optics, dispersion is the phenomenon in which the phase velocity of a
wave depends on its frequency,["

S*

Speed of waves
 

"Jim Lux" napisal w wiadomosci
...

Where dispersion becomes interesting (and is actually measured) is
when comparing signals at two separated frequencies, e.g. 8.4 GHz and
32 GHz. Or, for a closer to earth example, L1 & L2 for GPS (separated
by a couple hundred MHz at 1500 MHz) allow for compensation for
ionospheric delays.

It is what I was looking for.
Speed of all waves are frequency, amplitude and temperature dependent.
I realize that for radio waves the effects are small. It seems that for
radio amateurs too small.
GPS is extremely precise and there the effects must be measured.
Thanks you very much.

Best Regards,
S*

Speed of waves
 

On 25 mar, 16:46, wrote:
Szczepan Bialek wrote:
I am simple asking if radio people have trouble with the fact that the speed
of waves are frequeny dependent.

No, they are not because the speed of electromagnetic waves is NOT frequeny
dependent, the speed is media dependent, you babbling, ignorant, trolling,
moron.

--
Jim Pennino

Remove .spam.sux to reply.

Hello Jim,

Given a certain medium, both phase and group velocity can be frequency
dependent (example: ionosphere).

DRM uses OFDM to achieve very low baudrate to mitigate the dispersive
behavior of ionospheric propopation. A least 88 subcarriers are in 10
kHz bandwidth.

Wim
PA3DJS
www.tetech.nl

Speed of waves
 

In message , Szczepan Bialek
writes
"This finding had practical applications for telegraph communications. For
example, Heaviside actually solved one of the biggest problems affecting
long distance telegraph and telephone communication in 1887 -distortion. It
was known that different frequencies travel with different speeds on a long
cable. For example, the low bass frequencies in a voice signal travel faster
than the high treble frequencies. When the cable is long enough, the
frequencies smear, and both voice and telegraph signals become garbled
noise. Heaviside used his equations to show that if inductances (i.e., a
small coil of wire) were added along the length of the cable, the distortion
could be reduced." From:
http://www.ieeeghn.org/wiki/index.php/Oliver_Heaviside

" It was known that different frequencies travel with different speeds on a
long cable".

Is the same in air and space?

Yes in air , and no in space.

B
--
Brian Howie

Speed of waves
 

"Brian Howie" napisal w wiadomosci
...
In message , Szczepan Bialek
writes
"This finding had practical applications for telegraph communications. For
example, Heaviside actually solved one of the biggest problems affecting
long distance telegraph and telephone communication in 1887 -distortion.
It
was known that different frequencies travel with different speeds on a
long
cable. For example, the low bass frequencies in a voice signal travel
faster
than the high treble frequencies. When the cable is long enough, the
frequencies smear, and both voice and telegraph signals become garbled
noise. Heaviside used his equations to show that if inductances (i.e., a
small coil of wire) were added along the length of the cable, the
distortion
could be reduced." From:
http://www.ieeeghn.org/wiki/index.php/Oliver_Heaviside

" It was known that different frequencies travel with different speeds on
a
long cable".

Is the same in air and space?

Yes in air , and no in space.

Yes close to the Earth. But what is close to the Sun?
S*

Speed of waves
 

Wimpie wrote:
On 25 mar, 16:46, wrote:
Szczepan Bialek wrote:
I am simple asking if radio people have trouble with the fact that the speed
of waves are frequeny dependent.

No, they are not because the speed of electromagnetic waves is NOT frequeny
dependent, the speed is media dependent, you babbling, ignorant, trolling,
moron.

--
Jim Pennino

Remove .spam.sux to reply.

Hello Jim,

Given a certain medium, both phase and group velocity can be frequency
dependent (example: ionosphere).

The speed of light is media dependent.

The media may or may not have characteristics that are frequency dependent.

Cart - Horse.


--
Jim Pennino

Remove .spam.sux to reply.

Speed of waves
 

Brian Howie wrote:

" It was known that different frequencies travel with different speeds
on a
long cable".

Is the same in air and space?

Yes in air , and no in space.

B

Depends what you mean by "space".. perfect vacuum, sure..

But what's between the planets in the Solar System isn't a perfect
vacuum, and so, it shows dispersion due to the presence of small amounts
of ionization.

Granted, it's generally a better vacuum than you are likely to achieve
on Earth by mechanical means.

Speed of waves
 

"Jim Lux" napisal w wiadomosci
...
Brian Howie wrote:

" It was known that different frequencies travel with different speeds
on a
long cable".

Is the same in air and space?

Yes in air , and no in space.

B

Depends what you mean by "space".. perfect vacuum, sure..

But what's between the planets in the Solar System isn't a perfect vacuum,
and so, it shows dispersion due to the presence of small amounts of
ionization.

Granted, it's generally a better vacuum than you are likely to achieve on
Earth by mechanical means.

Speed of waves in a dispersive medium is temperature dependent.
In the Solar System the temperatures are decreasing with the distance from
the Sun.

You have send us: http://ipnpr.jpl.nasa.gov/progress_report/42-65/65I.PDF

It seems to me that the no answer for Maxwell's question:
"Incidentally, Maxwell once suggested that Roemer's method could be used to
test for the isotropy of light speed, i.e., to test whether the speed of
light is the same in all directions. Roemer's method can be regarded as a
means of measuring the speed of light in the direction from Jupiter to the
Earth. Jupiter has an orbital period of about 12 years, so if we use
Roemer's method to evaluate the speed of light several times over a 12 year
period, we will be evaluating the speed in all possible directions (in the
plane of the ecliptic). "

Do you know the answer?
S*

Speed of waves
 

Szczepan Bialek wrote:
"Jim Lux" napisal w wiadomosci
...
Brian Howie wrote:

" It was known that different frequencies travel with different speeds
on a
long cable".

Is the same in air and space?
Yes in air , and no in space.

B
Depends what you mean by "space".. perfect vacuum, sure..

But what's between the planets in the Solar System isn't a perfect vacuum,
and so, it shows dispersion due to the presence of small amounts of
ionization.

Granted, it's generally a better vacuum than you are likely to achieve on
Earth by mechanical means.

Speed of waves in a dispersive medium is temperature dependent.

Maybe.. depends on the medium, I should think, and the mechanism of the
dispersion. Some dispersion might be due to ionization (which may or
may not be temperature dependent).

In the Solar System the temperatures are decreasing with the distance from
the Sun.


Temperature in a vacuum and with ionized particles is tricky to define.
It has to do with mean free path and the velocity of the particles.
When the number density gets down in the "few atoms per cubic meter" and
the mean free path gets to be meters or km, I think you need to start
thinking in different ways.

One common confusion is an assumption of a particular velocity
distribution in charged particles and then using the 11000K = 1 eV relation.

Speed of waves
 

"Jim Lux" napisal w wiadomosci
...
Szczepan Bialek wrote:

Speed of waves in a dispersive medium is temperature dependent.

Maybe.. depends on the medium, I should think, and the mechanism of the
dispersion. Some dispersion might be due to ionization (which may or may
not be temperature dependent).

It is known that the speed of light in air is temperature dependent ( mirage
and E. Schmidt's method in Fluid dynamics).
in vacuum also. But I culd find the results.

In the Solar System the temperatures are decreasing with the distance
from the Sun.


Temperature in a vacuum and with ionized particles is tricky to define.
It has to do with mean free path and the velocity of the particles. When
the number density gets down in the "few atoms per cubic meter" and the
mean free path gets to be meters or km, I think you need to start thinking
in different ways.

May be, but at first I must know if the mirage works in vacuum.

One common confusion is an assumption of a particular velocity
distribution in charged particles and then using the 11000K = 1 eV
relation.

Yes. But the simple measurement of the mirage or E. Schmidt's effect in
vacuum will clarify everything.
"I am sure that such experiments were done". Could you help?
S*

Speed of waves
 

Szczepan Bialek wrote:
"Jim Lux" napisal w wiadomosci
...
Szczepan Bialek wrote:
Speed of waves in a dispersive medium is temperature dependent.
Maybe.. depends on the medium, I should think, and the mechanism of the
dispersion. Some dispersion might be due to ionization (which may or may
not be temperature dependent).

It is known that the speed of light in air is temperature dependent ( mirage
and E. Schmidt's method in Fluid dynamics).
in vacuum also. But I culd find the results.
In the Solar System the temperatures are decreasing with the distance
from the Sun.

Temperature in a vacuum and with ionized particles is tricky to define.
It has to do with mean free path and the velocity of the particles. When
the number density gets down in the "few atoms per cubic meter" and the
mean free path gets to be meters or km, I think you need to start thinking
in different ways.

May be, but at first I must know if the mirage works in vacuum.
One common confusion is an assumption of a particular velocity
distribution in charged particles and then using the 11000K = 1 eV
relation.

Yes. But the simple measurement of the mirage or E. Schmidt's effect in
vacuum will clarify everything.
"I am sure that such experiments were done". Could you help?
S*



How about Ordinary and Extraordinary rays in the dispersive medium of
the ionosphere. Is the ionosphere "vacuum" enough for you? The space
station orbits in the middle of it, and most folks think that qualifies
as vacuum (1e-6 Torr, or so). Electron density runs pretty high: about
1E10-1E12/m3

At the top, the pressure runs about 1E-5 Pascal (7.5E-8 torr) & mean
free path is on the order of tens of km.


There's lots and lots and lots of data about dispersion of EM
propagation in the ionosphere.

Again, I'm not sure "temperature" is the relevant measure for something
like that. You can define temperature for a very low pressure gas like
this, but it's not in the same sort of sense as one would apply to a
bulk tangible medium (like air at the Earth's surface or water)

Speed of waves
 

On 3/30/2011 11:50 AM, Jim Lux wrote:
Szczepan Bialek wrote:
"Jim Lux" napisal w wiadomosci
...
Szczepan Bialek wrote:
Speed of waves in a dispersive medium is temperature dependent.
Maybe.. depends on the medium, I should think, and the mechanism of
the dispersion. Some dispersion might be due to ionization (which may
or may not be temperature dependent).

It is known that the speed of light in air is temperature dependent (
mirage and E. Schmidt's method in Fluid dynamics).
in vacuum also. But I culd find the results.
In the Solar System the temperatures are decreasing with the
distance from the Sun.

Temperature in a vacuum and with ionized particles is tricky to define.
It has to do with mean free path and the velocity of the particles.
When the number density gets down in the "few atoms per cubic meter"
and the mean free path gets to be meters or km, I think you need to
start thinking in different ways.


(snip)


Again, I'm not sure "temperature" is the relevant measure for something
like that. You can define temperature for a very low pressure gas like
this, but it's not in the same sort of sense as one would apply to a
bulk tangible medium (like air at the Earth's surface or water)

Isaac Asimov touched on this in his book on physics. He said the
temperature up there is high because of the high molecule velocity, but
that *heat* is another matter. So, you can have a high "temperature"
even if the "heat" is practically nil.

That makes you correct. One must carefully state what is meant by
temperature and what is meant by heat.

Speed of waves
 

On 3/30/2011 1:04 PM, John - KD5YI wrote:
On 3/30/2011 11:50 AM, Jim Lux wrote:
Szczepan Bialek wrote:
"Jim Lux" napisal w wiadomosci
...
Szczepan Bialek wrote:
Speed of waves in a dispersive medium is temperature dependent.
Maybe.. depends on the medium, I should think, and the mechanism of
the dispersion. Some dispersion might be due to ionization (which may
or may not be temperature dependent).

It is known that the speed of light in air is temperature dependent (
mirage and E. Schmidt's method in Fluid dynamics).
in vacuum also. But I culd find the results.
In the Solar System the temperatures are decreasing with the
distance from the Sun.

Temperature in a vacuum and with ionized particles is tricky to define.
It has to do with mean free path and the velocity of the particles.
When the number density gets down in the "few atoms per cubic meter"
and the mean free path gets to be meters or km, I think you need to
start thinking in different ways.


(snip)


Again, I'm not sure "temperature" is the relevant measure for something
like that. You can define temperature for a very low pressure gas like
this, but it's not in the same sort of sense as one would apply to a
bulk tangible medium (like air at the Earth's surface or water)

Isaac Asimov touched on this in his book on physics. He said the
temperature up there is high because of the high molecule velocity, but
that *heat* is another matter.

because of extremely low molecular density at that altitude.

So, you can have a high "temperature"
even if the "heat" is practically nil.



That makes you correct. One must carefully state what is meant by
temperature and what is meant by heat.

Speed of waves
 

John - KD5YI wrote:


Again, I'm not sure "temperature" is the relevant measure for something
like that. You can define temperature for a very low pressure gas like
this, but it's not in the same sort of sense as one would apply to a
bulk tangible medium (like air at the Earth's surface or water)

Isaac Asimov touched on this in his book on physics. He said the
temperature up there is high because of the high molecule velocity, but
that *heat* is another matter. So, you can have a high "temperature"
even if the "heat" is practically nil.


I suppose, too, that the whole things still works in terms of, say,
propagation velocity of sound, because that is driven by velocity of
molecules/atoms (and is related to square root of Temperature).

So, sound propagates very quickly in the ionosphere (it's got a fairly
high temperature), but because there's not a whole lot of atoms around,
the attenuation will be quite high (essentially infinite, I suspect)

And that's totally different than propagating something by EM waves.



That makes you correct. One must carefully state what is meant by
temperature and what is meant by heat.

Speed of waves
 

"Jim Lux" napisal w wiadomosci
...
John - KD5YI wrote:


Again, I'm not sure "temperature" is the relevant measure for something
like that. You can define temperature for a very low pressure gas like
this, but it's not in the same sort of sense as one would apply to a
bulk tangible medium (like air at the Earth's surface or water)

Isaac Asimov touched on this in his book on physics. He said the
temperature up there is high because of the high molecule velocity, but
that *heat* is another matter. So, you can have a high "temperature" even
if the "heat" is practically nil.


I suppose, too, that the whole things still works in terms of, say,
propagation velocity of sound, because that is driven by velocity of
molecules/atoms (and is related to square root of Temperature).

Faraday supposed that this apply to the electric waves. Of course there the
electrons vibrate. The relation to temperature of electrons would be easy to
measure.

So, sound propagates very quickly in the ionosphere (it's got a fairly
high temperature), but because there's not a whole lot of atoms around,
the attenuation will be quite high (essentially infinite, I suspect)

No. Acoustic waves from the Sun (aurora) are et the Earth quite strong.

And that's totally different than propagating something by EM waves.

Electric waves propagate in metal and in space. In the both media the
electrons vibrate. "I suppose we may compare together the matter of the
aether and ordinary matter (as, for instance, the copper of the wire through
which the electricity is conducted), and consider them as alike in their
essential constitution"(Faraday).


That makes you correct. One must carefully state what is meant by
temperature and what is meant by heat.

It would be easy after Schmidt's experiment in vacuum. There the hot cylider
in air bends the light rays and the shadow diameter is bigger than for the
cold cylinder.
The same experiment in vacuum tell us if speed of light is electrons
temperature dependent.
S*

Speed of waves
 

Szczepan Bialek wrote:
"Jim Lux" napisal w wiadomosci
...
John - KD5YI wrote:

Again, I'm not sure "temperature" is the relevant measure for something
like that. You can define temperature for a very low pressure gas like
this, but it's not in the same sort of sense as one would apply to a
bulk tangible medium (like air at the Earth's surface or water)
Isaac Asimov touched on this in his book on physics. He said the
temperature up there is high because of the high molecule velocity, but
that *heat* is another matter. So, you can have a high "temperature" even
if the "heat" is practically nil.

I suppose, too, that the whole things still works in terms of, say,
propagation velocity of sound, because that is driven by velocity of
molecules/atoms (and is related to square root of Temperature).

Faraday supposed that this apply to the electric waves.

He was wrong.

Of course there the
electrons vibrate. The relation to temperature of electrons would be easy to
measure.


No, you have this wrong.


So, sound propagates very quickly in the ionosphere (it's got a fairly
high temperature), but because there's not a whole lot of atoms around,
the attenuation will be quite high (essentially infinite, I suspect)

No. Acoustic waves from the Sun (aurora) are et the Earth quite strong.

"acoustic waves" whatever you think they are do not propagate through a
vacuum. The aurora is NOT caused by acoustic waves.


And that's totally different than propagating something by EM waves.

Electric waves propagate in metal and in space. In the both media the
electrons vibrate.

But that is not how the waves propagate. In either material.


"I suppose we may compare together the matter of the
aether and ordinary matter (as, for instance, the copper of the wire through
which the electricity is conducted), and consider them as alike in their
essential constitution"(Faraday).

But this is wrong. You refuse to accept that 100+ year old statements
may be, and quite often are, wrong.


That makes you correct. One must carefully state what is meant by
temperature and what is meant by heat.

It would be easy after Schmidt's experiment in vacuum. There the hot cylider
in air bends the light rays and the shadow diameter is bigger than for the
cold cylinder.
The same experiment in vacuum tell us if speed of light is electrons
temperature dependent.

If you spent some time to understand the basic concepts, you might
realize just how wrong you are.


S*



What is the point of all this? You refuse to try to understand the basic
concepts, yet want to dig into the more esoteric stuff.

Speed of waves
 

"joe" napisal w wiadomosci
...
Szczepan Bialek wrote:
"Jim Lux" napisal w wiadomosci
...
John - KD5YI wrote:

Again, I'm not sure "temperature" is the relevant measure for
something
like that. You can define temperature for a very low pressure gas like
this, but it's not in the same sort of sense as one would apply to a
bulk tangible medium (like air at the Earth's surface or water)
Isaac Asimov touched on this in his book on physics. He said the
temperature up there is high because of the high molecule velocity, but
that *heat* is another matter. So, you can have a high "temperature"
even if the "heat" is practically nil.

I suppose, too, that the whole things still works in terms of, say,
propagation velocity of sound, because that is driven by velocity of
molecules/atoms (and is related to square root of Temperature).

Faraday supposed that this apply to the electric waves.

He was wrong.

Why. Molecules and ions vibrate. Electrons also.

Of course there the
electrons vibrate. The relation to temperature of electrons would be easy
to measure.


No, you have this wrong.


So, sound propagates very quickly in the ionosphere (it's got a fairly
high temperature), but because there's not a whole lot of atoms around,
the attenuation will be quite high (essentially infinite, I suspect)

No. Acoustic waves from the Sun (aurora) are at the Earth quite strong.

"acoustic waves" whatever you think they are do not propagate through a
vacuum.

"The Earth is constantly immersed in the solar wind, a rarefied flow of hot
plasma (gas of free electrons and positive ions) emitted by the Sun in all
directions, a result of the two-million-degree heat of the Sun's outermost
layer, the corona. The solar wind usually reaches Earth with a velocity
around 400 km/s, density around 5 ions/cm3 and magnetic field intensity
around 2-5 nT (nanoteslas; Earth's surface field is typically 30,000-50,000
nT). These are typical values. During magnetic storms, in particular, flows
can be several times faster; the interplanetary magnetic field (IMF) may
also be much stronger."

The aurora is NOT caused by acoustic waves.

" In the explosive event that a coronal mass ejection (CME) is reported it's
time to hop into action because this super-charged solar wind is traveling
fast (maybe 3-to-5 million miles per hour). When this energy sweeps by the
earth 1-to-3 nights later there is a very good chance of aurora activity".
From: http://aurorahunter.com/aurora-prediction.php

Do you think that ions and atoms in the solar wind do not vibrate?



And that's totally different than propagating something by EM waves.

Electric waves propagate in metal and in space. In the both media the
electrons vibrate.

But that is not how the waves propagate. In either material.

How then?


"I suppose we may compare together the matter of the
aether and ordinary matter (as, for instance, the copper of the wire
through which the electricity is conducted), and consider them as alike
in their essential constitution"(Faraday).

But this is wrong. You refuse to accept that 100+ year old statements may
be, and quite often are, wrong.

Heaviside's statements are also old.


That makes you correct. One must carefully state what is meant by
temperature and what is meant by heat.

It would be easy after Schmidt's experiment in vacuum. There the hot
cylider in air bends the light rays and the shadow diameter is bigger
than for the cold cylinder.
The same experiment in vacuum tell us if speed of light is electrons
temperature dependent.

If you spent some time to understand the basic concepts, you might realize
just how wrong you are.


What is the point of all this? You refuse to try to understand the basic
concepts, yet want to dig into the more esoteric stuff.

The topic is: " It was known that different frequencies travel with
different speeds on a
long cable".

Is the same in air and space?"

The answers were YES.

What do you want to add?
S*

Speed of waves
 

Szczepan Bialek wrote:


"The Earth is constantly immersed in the solar wind, a rarefied flow of hot
plasma (gas of free electrons and positive ions) emitted by the Sun in all
directions, a result of the two-million-degree heat of the Sun's outermost
layer, the corona. The solar wind usually reaches Earth with a velocity
around 400 km/s, density around 5 ions/cm3 and magnetic field intensity
around 2-5 nT (nanoteslas; Earth's surface field is typically 30,000-50,000
nT). These are typical values. During magnetic storms, in particular, flows
can be several times faster; the interplanetary magnetic field (IMF) may
also be much stronger."


Sure... the number density of ionized particles is somewhat bigger than
the 5/cc you describe above, so solar wind is actually not a big
contributor to it. Most of the ionization comes from UV ionizing the
air atoms/molecules. (that's what the whole daytime sky wave off the F
layer is all about, after all.. working Australia from the California on
20 meters at 5AM CA time probably isn't a good bet)



The aurora is NOT caused by acoustic waves.

" In the explosive event that a coronal mass ejection (CME) is reported it's
time to hop into action because this super-charged solar wind is traveling
fast (maybe 3-to-5 million miles per hour). When this energy sweeps by the
earth 1-to-3 nights later there is a very good chance of aurora activity".
From: http://aurorahunter.com/aurora-prediction.php


That's not acoustic. That's just particles streaming out into space,
and because there's not many other particles to bump into, most of them
get to Earth

Speed of waves
 

"Jim Lux" napisal w wiadomosci
...
Szczepan Bialek wrote:


"The Earth is constantly immersed in the solar wind, a rarefied flow of
hot plasma (gas of free electrons and positive ions) emitted by the Sun
in all directions, a result of the two-million-degree heat of the Sun's
outermost layer, the corona. The solar wind usually reaches Earth with a
velocity around 400 km/s, density around 5 ions/cm3 and magnetic field
intensity around 2-5 nT (nanoteslas; Earth's surface field is typically
30,000-50,000 nT). These are typical values. During magnetic storms, in
particular, flows can be several times faster; the interplanetary
magnetic field (IMF) may also be much stronger."


Sure... the number density of ionized particles is somewhat bigger than
the 5/cc you describe above, so solar wind is actually not a big
contributor to it. Most of the ionization comes from UV ionizing the air
atoms/molecules. (that's what the whole daytime sky wave off the F layer
is all about, after all.. working Australia from the California on 20
meters at 5AM CA time probably isn't a good bet)

In space is also the dust. The ionized particles can come from them also.
The Moon is a big dust.

The aurora is NOT caused by acoustic waves.

" In the explosive event that a coronal mass ejection (CME) is reported
it's time to hop into action because this super-charged solar wind is
traveling fast (maybe 3-to-5 million miles per hour). When this energy
sweeps by the earth 1-to-3 nights later there is a very good chance of
aurora activity". From: http://aurorahunter.com/aurora-prediction.php


That's not acoustic. That's just particles streaming out into space, and
because there's not many other particles to bump into, most of them get to
Earth

Cars produce the hot wind (exhaust pipe) with the acoustic waves. Is
possible to produce only streaming?
There must be the oscillatory flow.
S*

Speed of waves
 

On Apr 2, 7:48*am, "Szczepan Bialek" wrote:
*"Jim Lux" napisal w ...



Szczepan Bialek wrote:

"The Earth is constantly immersed in the solar wind, a rarefied flow of
hot plasma (gas of free electrons and positive ions) emitted by the Sun
in all directions, a result of the two-million-degree heat of the Sun's
outermost layer, the corona. The solar wind usually reaches Earth with a
velocity around 400 km/s, density around 5 ions/cm3 and magnetic field
intensity around 2-5 nT (nanoteslas; Earth's surface field is typically
30,000-50,000 nT). These are typical values. During magnetic storms, in
particular, flows can be several times faster; the interplanetary
magnetic field (IMF) may also be much stronger."

Sure... the number density of ionized particles is somewhat bigger than
the 5/cc you describe above, so solar wind is actually not a big
contributor to it. *Most of the ionization comes from UV ionizing the air
atoms/molecules. *(that's what the whole daytime sky wave off the F layer
is all about, after all.. working Australia from the California on 20
meters at 5AM CA time probably isn't a good bet)

In space is also the dust. The *ionized particles can come from them also.
The Moon is a big dust.



The aurora is NOT caused by acoustic waves.

" In the explosive event that a coronal mass ejection (CME) is reported
it's time to hop into action because this super-charged solar wind is
traveling fast (maybe 3-to-5 million miles per hour). When this energy
sweeps by the earth 1-to-3 nights later there is a very good chance of
aurora activity". From:http://aurorahunter.com/aurora-prediction.php

That's not acoustic. *That's just particles streaming out into space, and
because there's not many other particles to bump into, most of them get to
Earth

Cars produce the hot wind (exhaust pipe) with the acoustic waves. Is
possible to produce only streaming?
There must be the oscillatory flow.
S*

you produce hot wind also... you should learn to listen and get into
this century. no, the solar wind is not oscillatory, it flows from
the sun all the way past pluto. it also varies in speed quite a bit
so if the light was being propagated by the particles in the solar
wind we would see large changes in the velocity and intensity coming
from the sun that would be very easy to measure, and would likely have
killed off all life long ago.

Speed of waves
 

napisal w wiadomosci
...
On Apr 2, 7:48 am, "Szczepan Bialek" wrote:
"Jim Lux" napisal w
...



Szczepan Bialek wrote:

"The Earth is constantly immersed in the solar wind, a rarefied flow of
hot plasma (gas of free electrons and positive ions) emitted by the Sun
in all directions, a result of the two-million-degree heat of the Sun's
outermost layer, the corona. The solar wind usually reaches Earth with
a
velocity around 400 km/s, density around 5 ions/cm3 and magnetic field
intensity around 2-5 nT (nanoteslas; Earth's surface field is typically
30,000-50,000 nT). These are typical values. During magnetic storms, in
particular, flows can be several times faster; the interplanetary
magnetic field (IMF) may also be much stronger."

Sure... the number density of ionized particles is somewhat bigger than
the 5/cc you describe above, so solar wind is actually not a big
contributor to it. Most of the ionization comes from UV ionizing the air
atoms/molecules. (that's what the whole daytime sky wave off the F layer
is all about, after all.. working Australia from the California on 20
meters at 5AM CA time probably isn't a good bet)

In space is also the dust. The ionized particles can come from them also.
The Moon is a big dust.



The aurora is NOT caused by acoustic waves.

" In the explosive event that a coronal mass ejection (CME) is reported
it's time to hop into action because this super-charged solar wind is
traveling fast (maybe 3-to-5 million miles per hour). When this energy
sweeps by the earth 1-to-3 nights later there is a very good chance of
aurora activity". From: http://aurorahunter.com/aurora-prediction.php

That's not acoustic. That's just particles streaming out into space, and
because there's not many other particles to bump into, most of them get
to
Earth

Cars produce the hot wind (exhaust pipe) with the acoustic waves. Is
possible to produce only streaming?
There must be the oscillatory flow.
S*

you produce hot wind also...

But also with nois.

you should learn to listen and get into this century. no, the solar wind
is not oscillatory,

Yes. But if no the sunspost (explosions).

it flows from the sun all the way past pluto. it also varies in speed
quite a bit
so if the light was being propagated by the particles in the solar
wind we would see large changes in the velocity and intensity coming
from the sun that would be very easy to measure

Good idea. Have you a procedure for such measurements. But the changes are
rather small.

, and would likely have killed off all life long ago.

The changes makes auroras only.
S*

Speed of waves
 

On Apr 2, 4:05*pm, "Szczepan Bialek" wrote:
napisal w ...
On Apr 2, 7:48 am, "Szczepan Bialek" wrote:



"Jim Lux" napisal w
...

Szczepan Bialek wrote:

"The Earth is constantly immersed in the solar wind, a rarefied flow of
hot plasma (gas of free electrons and positive ions) emitted by the Sun
in all directions, a result of the two-million-degree heat of the Sun's
outermost layer, the corona. The solar wind usually reaches Earth with
a
velocity around 400 km/s, density around 5 ions/cm3 and magnetic field
intensity around 2-5 nT (nanoteslas; Earth's surface field is typically
30,000-50,000 nT). These are typical values. During magnetic storms, in
particular, flows can be several times faster; the interplanetary
magnetic field (IMF) may also be much stronger."

Sure... the number density of ionized particles is somewhat bigger than
the 5/cc you describe above, so solar wind is actually not a big
contributor to it. Most of the ionization comes from UV ionizing the air
atoms/molecules. (that's what the whole daytime sky wave off the F layer
is all about, after all.. working Australia from the California on 20
meters at 5AM CA time probably isn't a good bet)

In space is also the dust. The ionized particles can come from them also.
The Moon is a big dust.

The aurora is NOT caused by acoustic waves.

" In the explosive event that a coronal mass ejection (CME) is reported
it's time to hop into action because this super-charged solar wind is
traveling fast (maybe 3-to-5 million miles per hour). When this energy
sweeps by the earth 1-to-3 nights later there is a very good chance of
aurora activity". From: *http://aurorahunter.com/aurora-prediction..php

That's not acoustic. That's just particles streaming out into space, and
because there's not many other particles to bump into, most of them get
to
Earth

Cars produce the hot wind (exhaust pipe) with the acoustic waves. Is
possible to produce only streaming?
There must be the oscillatory flow.
S*

you produce hot wind also...

But also with nois.

you should learn to listen and get into this century. *no, the solar wind
is not oscillatory,

Yes. But if no the sunspost (explosions).

it flows from the sun all the way past pluto. *it also varies in speed
quite a bit
so if the light was being propagated by the particles in the solar
wind we would see large changes in the velocity and intensity coming
from the sun that would be very easy to measure

Good idea. Have you a procedure for such measurements. But the changes are
rather small.

, and would likely have killed off all life long ago.

The changes makes auroras only.
S*

no, the changes don't always make aurora, and they are definately NOT
small. watch the speed on this for a few months, even without aurora
and see how much it changes. if the waves were traveling on the
charged particles then they would change speed just as much:
http://www.swpc.noaa.gov/ace/MAG_SWEPAM_24h.html

Speed of waves
 

napisal w wiadomosci
...
On Apr 2, 4:05 pm, "Szczepan Bialek" wrote:

The changes makes auroras only.
S*

no, the changes don't always make aurora, and they are definately NOT
small. watch the speed on this for a few months, even without aurora
and see how much it changes. if the waves were traveling on the
charged particles then they would change speed just as much:
http://www.swpc.noaa.gov/ace/MAG_SWEPAM_24h.html

"A large solar flare jettisoned from the sun, striking the Earth four days
later"

Read mo Effects of Solar Wind | eHow.com
http://www.ehow.com/about_5124161_ef...#ixzz1ITcThhIf

150 000 000km / 4days = 150 000 000 / 350 000s = 430 km/s.

For you it is the speed of the solar wind.
For me it is the speed of acoustic waves.

According to Faraday and today scientist the plasma is like metal.
Ions are the medium for acoustic waves and electrons for the electric (in
metals and in plasma).

Have you a link with the method for measure the speed of solar wind?

S*

Speed of waves
 

On Apr 3, 4:26*pm, "Szczepan Bialek" wrote:
napisal w ...
On Apr 2, 4:05 pm, "Szczepan Bialek" wrote:



The changes makes auroras only.
S*
no, the changes don't always make aurora, and they are definately NOT

small. *watch the speed on this for a few months, even without aurora
and see how much it changes. *if the waves were traveling on the
charged particles then they would change speed just as much:http://www.swpc.noaa.gov/ace/MAG_SWEPAM_24h.html

"A large solar flare jettisoned from the sun, striking the Earth four days
later"

Read mo Effects of Solar Wind | eHow.comhttp://www.ehow.com/about_5124161_effects-solar-wind.html#ixzz1ITcThhIf

150 000 000km / 4days = 150 000 000 / 350 000s = 430 km/s.

For you it is the speed of the solar wind.
For me it is the speed of acoustic waves.

According to Faraday and today scientist the plasma is like metal.
Ions are the medium for acoustic waves and electrons for the electric (in
metals and in plasma).

Have *you a link with the method for measure the speed of solar wind?

S*

go to that link i gave you above, the 'normal' speed of the solar wind
like now is over 500km/s, it gets much faster when there is a coronal
hole or from a cme.