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Spacecraft Doppler&Light Speed Extrapolation



 
 
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  #1  
Old July 7th 03, 03:53 PM
ralph sansbury
external usenet poster
 
Posts: n/a
Default Spacecraft Doppler&Light Speed Extrapolation

George Dishman suggested to me that Doppler signals sent to
a spacecraft and relayed back to earth would provide a good
test of the instantaneous speed of light hypothesis.
That hypothesis states that the r/c delay in light does not
extrapolate
beyond c but at great distances does not increase beyond a
maximal value. Thus a
light source, 30 time 10^8 meters away, like a source 3 times
10^8
meters away still produces an effect in a second (due to
instantaneous forces that produce a cumulative effect rising
above threshold after such a one second at most delay)
The problem with this proposed test is that Doppler data
that is inconsistent with the speed of light assumptions is
partially or entirely filtered out by NASA.
According to Morabito-Asmar(see Google) paper "The
closed-loop NASA tracking system produces Doppler counts,
Doppler
"pseudoresiduals"( residual based on predicted frequencies used
to tune the receivers),signal strengths(AGCs) and Doppler
reference frequencies either in the form of a constant
frequency or uplink ramps." All this is output on a so called
ATDF tape ,
so frequencies that are too far from the predicted shifted
frequency may be filtered out.
( I am assuming that in this process the carrier frequency is
modulated
so that when a resonant increase of a specific incoming frequency
is produced
it is not Johnson noise or whatever but the code modulated
carrier from the
spacecraft. I am also assuming that tuning around the predicted
shift will occur
so that even if the incoming frequency is not too far from the
predicted frequency it can still be obtained)
Craig Marquardt has further filtered some of these files to
exclude the daily modulations due to the earth's spin, plus or
minus.5km/sec(plus or minus10kHz he claims although I dont
think this takes into account the enormous changes in the
projection
angle between the velocity of the earth and the line to the
spacecraft)
The result is another "data" file attempting to be consistent
with the
speed of light delay . The assumptions of the speed of light
delay are so built
into all of the data coming from NASA that it may be impossible
to
actually test the hypothesis that light is nearly instantaneous.
But lets see. I am told that at 7:38 Mar 7 1988,
rx=2.291710886.9109Hz.

From the telnet ephemeris I find that Pioneer 10 had the
following heliocentric,xyz, coordinates in AU units:
2447227.817361111, A.D. 1988-Mar-07 07:37:00.0000,
1.436437796483437E+01, 4.078001848489932E+01,
2.333352522486281E+00,
2447227.818055556, A.D. 1988-Mar-07 07:38:00.0000,
1.436438157235370E+01, 4.078003529995198E+01,
2.333352811320062E+00,
2447227.818750000, A.D. 1988-Mar-07 07:39:00.0000,
1.436438517997504E+01, 4.078005211560639E+01,
2.333353099907363E+00,
and that the Sun at the same time had :
2447227.817361111, A.D. 1988-Mar-07 07:37:00.0000,
9.674871050446867E-01, -2.212064445087720E-01,
3.105791038669308E-05,
2447227.818055556, A.D. 1988-Mar-07 07:38:00.0000,
9.674901060953275E-01, -2.211948077051214E-01,
3.108019085814273E-05,
2447227.818750000, A.D. 1988-Mar-07 07:39:00.0000,
9.674931072480047E-01, -2.211831702995969E-01,
3.110222484770500E-05,
and so Canberra in solar coordinates would have an x coordinate
which is the negative of the sun's x coordinate here etc.
From this data one gets the craft-site difference vector at
7:38 that represents the craft-site line "d" and the two time
difference vectors (7:38 and 7:37 etc) divided by 60 seconds
gives the speed
of the site,'vs', and the speed of the craft,'vc'.
The dot products of each velocity and the line "d" divided by
the sum of squares of coordinates of "d" gives the projections
of
these velocities on the line, "d" and the difference in these
projected
velocities gives the craft site relative velocity v which plugged
into the
formula above gives the predicted Doppler.
If the predicted Doppler here is close to the observed rx then
the instantaneous hypothesis is indicated.
The problem is to obtain from NASA the correct tx values??????










  #2  
Old July 7th 03, 04:42 PM
Sam Wormley
external usenet poster
 
Posts: n/a
Default Spacecraft Doppler&Light Speed Extrapolation


ralph sansbury wrote:

George Dishman suggested to me that Doppler signals sent to
a spacecraft and relayed back to earth would provide a good
test of the instantaneous speed of light hypothesis.


What folly--It's hard to understand why some folks (that appear to
be interested in physics) don't take the lime to learn any physics.
There are many wonderful physics books available in libraries and
bookstores at various levels.
http://math.ucr.edu/home/baez/physic..._booklist.html
  #3  
Old July 7th 03, 10:50 PM
George G. Dishman
external usenet poster
 
Posts: n/a
Default Spacecraft Doppler&Light Speed Extrapolation

"ralph sansbury" wrote in message ...
George Dishman suggested to me that Doppler signals sent to
a spacecraft and relayed back to earth would provide a good
test of the instantaneous speed of light hypothesis.
That hypothesis states that the r/c delay in light does not
extrapolate
beyond c but at great distances does not increase beyond a
maximal value. Thus a
light source, 30 time 10^8 meters away, like a source 3 times
10^8
meters away still produces an effect in a second (due to
instantaneous forces that produce a cumulative effect rising
above threshold after such a one second at most delay)


Both the conventional theory and Ralph's have been used
to produce predictions of the receive frequency for
days in March 1988.

http://www.briar.demon.co.uk/Ralph/1988_pred.gif

The blue lines are Ralph's while orange and magenta
are conventional. There are clear differences most
notably in the phase of the diurnal variation, hence
my recommendation.

The problem with this proposed test is that Doppler data
that is inconsistent with the speed of light assumptions is
partially or entirely filtered out by NASA.


That is not true. The data available from the NSSDC
includes _all_ results and it is up to the user to
perform the filtering.

According to Morabito-Asmar(see Google) paper "The
closed-loop NASA tracking system produces Doppler counts,
Doppler
"pseudoresiduals"( residual based on predicted frequencies used
to tune the receivers),signal strengths(AGCs) and Doppler
reference frequencies either in the form of a constant
frequency or uplink ramps." All this is output on a so called
ATDF tape ,


Note in particular this quote says that the signal
strength is obtained from the "AGC" meaning "Automatic
Gain Control". Looking at

http://spaceprojects.arc.nasa.gov/Sp...er/PNStat.html

"DSS 63 acquired the downlink on time at -183 dbm.
After peaking the signal to -178.5 dbm, they locked
the telemetry at 16 bps with SNR of -0.5 db."

Clearly, they first locked on to the RF signal before
attempting to detect the sub-carrier and the processes
are quite separate.

so frequencies that are too far from the predicted shifted
frequency may be filtered out.


Inspection of the data shows large tails on the
distribution so this is not the case.

( I am assuming that in this process the carrier frequency is
modulated
so that when a resonant increase of a specific incoming frequency
is produced
it is not Johnson noise or whatever but the code modulated
carrier from the
spacecraft.


The microwave carrier is modulated by a 16kHz sub-carrier
which is further modulated by the science data. Neither
modulation plays any part in the RF acquisition however,
as Ralph quoted above the RF signal level is measured
from the AGC circuit.

I am also assuming that tuning around the predicted
shift will occur
so that even if the incoming frequency is not too far from the
predicted frequency it can still be obtained)


The receiver searches to acquire the downlink signal
rather than 'tuning'.

Craig Marquardt


That should be Markwardt.

has further filtered some of these files to
exclude the daily modulations due to the earth's spin, plus or
minus.5km/sec(plus or minus10kHz he claims although I dont
think this takes into account the enormous changes in the
projection
angle between the velocity of the earth and the line to the
spacecraft)


Craig does not use a rotating coordinate system, nor
do I, so this change of angle is non-existent.

The result is another "data" file attempting to be consistent
with the
speed of light delay.


No, the filtering removes outliers far from the mean
of their neighbours, regardless of the speed of light.

The assumptions of the speed of light
delay are so built
into all of the data coming from NASA that it may be impossible
to
actually test the hypothesis that light is nearly instantaneous.


The data Ralph has is independent records of
a) transmit frequency with time of transmission
b) receive frequency with time of reception
so the speed of light doesn't come into the
picture at all up to this stage.

It is up to the user to determine, for any record
of a reception, when the corresponding transmission
ocurred and determine the transmit frequency
accordingly so if Ralph doesn't want to use the
speed of light, that is up to him.

Ralph knows all this already, we have been
discussing it for some months by email so why he
is making these statements he knows to be false.

But lets see. I am told that at 7:38 Mar 7 1988,
rx=2.291710886.9109Hz.

From the telnet ephemeris I find that Pioneer 10 had the
following heliocentric,xyz, coordinates in AU units:

snip
and that the Sun at the same time had :

snip
and so Canberra in solar coordinates would have an x coordinate
which is the negative of the sun's x coordinate here etc.


I think you must be giving geocentric, not heliocentric,
coordinates since you have no reference to the Earth or
sites in the above. That gives you a rotating reference
frame and may lead to other problems. I would suggest
using barycentric coordinates for the sites and craft
to reduce these risks.

From this data one gets the craft-site difference vector at
7:38 that represents the craft-site line "d" and the two time
difference vectors (7:38 and 7:37 etc) divided by 60 seconds
gives the speed
of the site,'vs', and the speed of the craft,'vc'.
The dot products of each velocity and the line "d" divided by
the sum of squares of coordinates of "d" gives the projections
of
these velocities on the line, "d" and the difference in these
projected
velocities gives the craft site relative velocity v which plugged
into the
formula above gives the predicted Doppler.


That is roughly right though your shorthand description
leaves a bit to the imagination. However, this can be
done by using Horizons directly by noting that the rate
of change of range is 42.51139km/s for Canberra at 07:38
on the 7th and 42.67846km/s for Madrid at 19:38 on the 6th.
(The round trip time was 12 hours by conventional theory.)

If the predicted Doppler here is close to the observed rx then
the instantaneous hypothesis is indicated.


Conversely if the actuals are closer to the conventional
prediction then your theory can be falsified. However
the coseness of a single reading is a poor indicator. The
key part of my suggestion was that the phase of the diurnal
variation directly indicates the longitude of the transmitter
for any assumption about the transmit time.

The problem is to obtain from NASA the correct tx values??????


Both sites transmitted at 2110883520Hz on both days so
there is no problem with that part. Again this information
is in the data Ralph received directly.

Two further pieces of information are required. First
there is a transponder ratio of 240:221 that must be
included in the predictions. Secondly Ralph, you haven't
stated the equation to be used for the speed-related
frequency shift in your theory, equivalent to Doppler
shift in conventional theory.

Other readers should note this is an approximate technique,
adequate for this purpose, but with several shortcomings
for more accurate work.

George
  #4  
Old July 8th 03, 04:30 PM
ralph sansbury
external usenet poster
 
Posts: n/a
Default Spacecraft Doppler&Light Speed Extrapolation


----- Original Message -----
From: "George G. Dishman"
Newsgroups: sci.astro,sci.physics
Sent: Monday, July 07, 2003 5:50 PM
Subject: Spacecraft Doppler&Light Speed Extrapolation


"ralph sansbury" wrote in message

...
George Dishman suggested to me that Doppler signals sent to
a spacecraft and relayed back to earth would provide a good
test of the instantaneous speed of light hypothesis.
That hypothesis states that the r/c delay in light does

not
extrapolate
beyond c but at great distances does not increase beyond a
maximal value. Thus a
light source, 30 time 10^8 meters away, like a source 3 times
10^8
meters away still produces an effect in a second (due to
instantaneous forces that produce a cumulative effect rising
above threshold after such a one second at most delay)


The problem with this proposed test is that Doppler

data
that is inconsistent with the speed of light assumptions is
partially or entirely filtered out by NASA.


According to Morabito-Asmar(see Google) paper "The
closed-loop NASA tracking system produces Doppler counts,
Doppler
"pseudoresiduals"( residual based on predicted frequencies

used
to tune the receivers),signal strengths(AGCs) and Doppler
reference frequencies either in the form of a constant
frequency or uplink ramps." All this is output on a so called
ATDF tape ,


Note in particular this quote says that the signal
strength is obtained from the "AGC" meaning "Automatic
Gain Control". Looking at


http://spaceprojects.arc.nasa.gov/Sp...oneer/PNStat.h
tml

"DSS 63 acquired the downlink on time at -183 dbm.
After peaking the signal to -178.5 dbm, they locked
the telemetry at 16 bps with SNR of -0.5 db."

This suggests that a frequency near the predicted frequency
has
been
resonated and that an AGC circuit to reduce strong local
interference
has been employed so that subsequently the modulation code or
signal
can be removed and identified if it is really there to confirm
that
the tuned resonant frequency is not Johnson noise.
Clearly, the filtering techniques of nasa and Marquardt
are as they say they are namely used to avoid data too far from
the
predicted frequencies.
In spite of this I have some hope that the accepted data
in some cases will show that the received Doppler could have
been produced a second before by the receiving station
if the receiving station was also actively transmitting
at the time of reception.

The data you have is filtered and modified even further by Craig
Marquardt as you know.

( I am assuming that in this process the carrier frequency

is
modulated
so that when a resonant increase of a specific incoming

frequency
is produced
it is not Johnson noise or whatever but the code modulated
carrier from the
spacecraft.
I am also assuming that tuning around the predicted

shift will occur
so that even if the incoming frequency is not too far from

the
predicted frequency it can still be obtained)
The result is another "data" file attempting to be

consistent
with the
speed of light delay.


No, the filtering removes outliers far from the mean
of their neighbours, regardless of the speed of light.


I disagree. Since this gets rid of neighbors that depart
the most from the predicted values based on the speed
of light assumptions.


The assumptions of the speed of light
delay are so built
into all of the data coming from NASA that it may be

impossible
to
actually test the hypothesis that light is nearly

instantaneous.
But lets see. I am told that at 7:38 Mar 7 1988,
rx=2.291710886.9109Hz.

From the telnet ephemeris I find that Pioneer 10 had the
following heliocentric,xyz, coordinates in AU units:

snip
and that the Sun at the same time had :

snip
and so Canberra in solar coordinates would have an x

coordinate
which is the negative of the sun's x coordinate here etc.


I think you must be giving geocentric, not heliocentric,
coordinates since you have no reference to the Earth or
sites in the above. That gives you a rotating reference
frame and may lead to other problems. I would suggest
using barycentric coordinates for the sites and craft
to reduce these risks.


The coordinates are what is available from telnet and since
relativistic considerations are not necessary here have no risks
..
xy-plane: plane of the Earth's orbit at the reference
epoch
x-axis : out along ascending node of instantaneous plane of
the
Earth's orbit and the Earth's mean equator at the reference
epoch
z-axis : perpendicular to the xy-plane in the directional (+
or -) sense
of Earth's north pole at the reference epoch.

From this data one gets the craft-site difference vector

at
7:38 that represents the craft-site line "d" and the two time
difference vectors (7:38 and 7:37 etc) divided by 60 seconds
gives the speed
of the site,'vs', and the speed of the craft,'vc'.
The dot products of each velocity and the line "d"

divided by
the sum of squares of coordinates of "d" gives the

projections
of
these velocities on the line, "d" and the difference in these
projected
velocities gives the craft site relative velocity v which

plugged
into the
formula above gives the predicted Doppler.




If the predicted Doppler here is close to the observed rx

then
the instantaneous hypothesis is indicated.


Conversely if the actuals are closer to the conventional
prediction then your theory can be falsified.


Unfortunately because of the- acknowledged by nasa and
Marquardt
but not by you- filtering process guarantees that the
conventional
prediction is also close. So this proves nothing about the
conventional
prediction.
It does however permit a falsification of my theory that the
r/c speed of light does not extrapolate beyond r=c and that the
Doppler
signal could have been received within seconds or not.

However
the coseness of a single reading is a poor indicator.

But there may be hundreds of close readings just like
this
perhaps which thus confirm the hypothesis. The fact that there
aren't
many more is because there are so many gaps in the data due to
failed
attempts to tune in predicted frequencies ( based on the mistaken
and
never tested theorythat the r/c speed of light extrapolates to
distances
greater than c.)



The problem is to obtain from NASA the correct tx

values??????

Both sites transmitted at 2110883520Hz on both days so
there is no problem with that part.


I take you at your word but would like to know what nasa
documents say this.



Two further pieces of information are required. First
there is a transponder ratio of 240:221 that must be
included in the predictions. Secondly Ralph, you haven't
stated the equation to be used for the speed-related
frequency shift in your theory, equivalent to Doppler
shift in conventional theory.

The Doppler shift equation is (1+v/c)f without
relativitistic
modifications which are unnecessary here where v here is the
difference
in the projections of vs an vc on the line d.
(1+v/c)f is received by the spacecraft and retransmitted as
(240/221)(1+v)f so that(1+ v)^2 times 24/221 times f should be
received by the sending site a second or so later if the sending
site
was also scheduled to send at this time of reception
v denotes the sum of the projected craft and earth site
velocities
on the instantaneous line, d.
Its easy to put the data and equations in a spreadsheet and
calculate the answer
But I would suggest using the least filtered data. I am
working on
that now


  #5  
Old July 9th 03, 07:38 AM
Craig Markwardt
external usenet poster
 
Posts: n/a
Default Spacecraft Doppler&Light Speed Extrapolation


"ralph sansbury" writes:
Clearly, the filtering techniques of nasa and Marquardt
are as they say they are namely used to avoid data too far from
the
predicted frequencies.


[ Note incorrect spellings of proper noun. ]

Your claims are unsubstantiated. Two kinds of filtering were applied.
The first kind excluded outliers from the local trend. No assumption
of light travel was made. The second kind of filtering removed noisy
outliers after a crude solution was already achieved without fitting.
A total of 76% of records passed.

On the other hand, as you are well awa

In 1987, Pioneer was below the horizon (i.e. blocked by the earth) as
seen by the uplink station, for 89% of the downlinks.

In 1988, that fraction goes up to 92%.

For the overall 1987 to 1994 timeframe, the average amount of time
this occurs is 85%.

The opposite situation, where Pioneer is below the horizon as seen by
the downlink station at the time of uplink, occurs 83% and 91% of the
time.

A general conclusion is that more than four fifths of the time between
1987 and 1994, the spacecraft is blocked from seeing one station at
the same time that the other station is actively up- or down-linking.


Therefore, it impossible for your putative scenario (i.e. nearly
instantaneous light propagation) to have happened, since radio waves
don't penetrate the earth. There is only a few per cents of the time
where the uplink and downlink station were in view of the Pioneer
spacecraft at the same time, and yet 76% of the data were good!! EVEN
WITHOUT EXCLUDING THE NOISY DATA, THE SOLUTION WAS STILL VALID (see
Markwardt 2002, sec. E).

Therefore, your claims are quite simply and utterly bogus.


[ Dishman: ]
No, the filtering removes outliers far from the mean
of their neighbours, regardless of the speed of light.


I disagree. Since this gets rid of neighbors that depart
the most from the predicted values based on the speed
of light assumptions.


Erroneous assumption, as noted above.



But there may be hundreds of close readings just like this
perhaps which thus confirm the hypothesis. The fact that there
aren't many more is because there are so many gaps in the data due
to failed attempts to tune in predicted frequencies ( based on the
mistaken and never tested theorythat the r/c speed of light
extrapolates to distances greater than c.)


Your "close readings" theory is unsubstantiated. The Pioneer 10
solution requires knowledge of earth motion, earth rotation, and
variations in earth rotation on the line of sight to less than 1
*millimeter* per second. It is not possible to get a close reading
just by chance. If light travel time were nearly instantaneous, the
linear speed of the earth would be incorrect by hundreds of *meters*
per second.


The problem is to obtain from NASA the correct tx

values??????

Both sites transmitted at 2110883520Hz on both days so
there is no problem with that part.


I take you at your word but would like to know what nasa
documents say this.


The transmitted frequency is not a matter of NASA documentation. It's
a matter of the Doppler tracking records, stored in the ATDF files.


The Doppler shift equation is (1+v/c)f without
relativitistic
modifications which are unnecessary here where v here is the
difference
in the projections of vs an vc on the line d.


I performed a test which showed that the relativistic form of the
Doppler shift are indeed required. The classical form leads to much
higher residuals.

CM
  #6  
Old July 9th 03, 02:09 PM
ralph sansbury
external usenet poster
 
Posts: n/a
Default Spacecraft Doppler&Light Speed Extrapolation


"Craig Markwardt" wrote in
message news

"ralph sansbury" writes:
Clearly, the filtering techniques of nasa and Markwardt
are as they say they are namely used to avoid data too far

from
the
predicted frequencies.







Your claims are unsubstantiated. Two kinds of filtering were

applied.
The first kind excluded outliers from the local trend. No

assumption
of light travel was made.


But these are outliers with respect to previously filtered
data required by the resonance frequencies used to tune the
receiver. and the intermediate frequency before further
processing. That implies they are outliers from the predicted
frequency.

The second kind of filtering removed noisy
outliers after a crude solution was already achieved without

fitting.
A total of 76% of records passed.

On the other hand, as you are well awa

In 1987,


We are talking about 1980.

Pioneer was below the horizon (i.e. blocked by the earth) as
seen by the uplink station, for 89% of the downlinks.


I am saying that what you think was the uplink station for a
specific reception was not the uplink station. The true uplink
station was the receiving station.
If that is the case the earth would not block reception. Do
you understand?


  #7  
Old July 9th 03, 06:22 PM
ralph sansbury
external usenet poster
 
Posts: n/a
Default Spacecraft Doppler&Light Speed Extrapolation


"ralph sansbury" wrote in message
...

"Craig Markwardt" wrote in
message news

"ralph sansbury" writes:
Clearly, the filtering techniques of nasa and

Markwardt
are as they say they are namely used to avoid data too far

from
the
predicted frequencies.







Your claims are unsubstantiated. Two kinds of filtering were

applied.
The first kind excluded outliers from the local trend. No

assumption
of light travel was made.


But these are outliers with respect to previously filtered
data required by the resonance frequencies used to tune the
receiver and the intermediate frequency before further
processing. That implies they are outliers from the predicted
frequency.

The second kind of filtering removed noisy
outliers after a crude solution was already achieved without

fitting.
A total of 76% of records passed.

On the other hand, as you are well awa

In 1987,


We are talking about 1980.


Sorry. We are not talking about 1980 but about 1987 and 1988.
But the horizon blocking of the uplink sites ( Calif and Madrid?)
for 89% of the assumed downlinks in Canberra does not matter.
I am assuming that when receptions are scheduled for a
specific craft of the many crafts out there that transmissions to
the same craft also occur at the same time in the interest of
efficiency.
So clearly there is no horizon earth blocking problem at the
time of reception!!!!!!!


Pioneer was below the horizon (i.e. blocked by the earth) as
seen by the uplink station, for 89% of the downlinks.


I am saying that what you think was the uplink station for

a
specific reception was not the uplink station. The true uplink
station was the receiving station.
If that is the case the earth would not block reception. Do
you understand?




  #8  
Old July 9th 03, 07:21 PM
ralph sansbury
external usenet poster
 
Posts: n/a
Default Spacecraft Doppler&Light Speed Extrapolation


"George G. Dishman" wrote in message
om...
"ralph sansbury" wrote in message

...
According to Morabito-Asmar(see Google) paper ..

Note in particular this quote says that the signal
strength is obtained from the "AGC" meaning "Automatic
Gain Control". Looking at


http://spaceprojects.arc.nasa.gov/Sp...oneer/PNStat.h
tml

"DSS 63 acquired the downlink on time at -183 dbm.
After peaking the signal to -178.5 dbm, they locked
the telemetry at 16 bps with SNR of -0.5 db."

This suggests that a frequency near the predicted

frequency
has
been
resonated and that an AGC circuit to reduce strong local
interference
has been employed so that subsequently the modulation code or
signal
can be removed and identified if it is really there to

confirm
that
the tuned resonant frequency is not Johnson noise.


No, the system is nothing like that. The front end
is wideband and uses an LNA, a Low Noise Amplifier,
to amplify the signal and pass it down to the
receiving equipment. The filtering is done there
as part of the digital PLL. All this is described
in the document you quoted Ralph. There is no
resonant circuit involved at all.

I cant believe a resonant circuit is not involved. This is
the basis of all radio and microwave communications. The gang
tuning of carrier frequency and the local oscillator at a fixed
difference below the carrier produces an intermediate frequency
and the modulations of the carrier,a pattern of zeros and ones I
suppose, that is produced by the transmitter on the uplink is
extracted by the diode and processed by the agc control circuit
etc. to indicate if the resonant carrier is not Johnson noise at
this frequency.
I have a book by Allan Scott on Understanding Microwaves that
describes the electronic tuning of the capacitance of varactor
diode with a pump frequency of twice the predicted frequency in
a cryogenic parametric amplifier so these adjusmentsare analagous
to those in gang tuning a radio circuit
The low noise amplification you are talking about depends on
resonance and so you are filtering out all frequencies too far
from the frequency predicted on the basis of the light speed
delay assumption and the frequency of that site

The AGC keeps the output of the early stages at a
constant amplitude so for pure noise you get some
level on the AGC line while in the presence of a
signal the gain is reduced and by using a circuit
with a well-defined relationship between control
voltage and gain, you know how much signal is
present.

If there was strong local noise, an AGC circuit
would discard the signal when the noise was present
giving the worst possible effect.


Just the opposite. A proportion of the rectified voltage coming
off the detector diode is fed back in such a way as lower the
bias potential of the base and prevent distortions from strong
local noise.

Clearly, the filtering techniques of nasa and Markwardt


are as they say they are namely used to avoid data too far

from
the predicted frequencies.


The DSN receiver filters the signal severely to
pull it out of the noise so part of what you
say is true. You might want to talk more about
that aspect.

The filtering Craig adds does not use the predicted
frequency AIUI but filters relative to the mean
(or median, I need to check his paper?) so does not
cause us a problem.

In spite of this I have some hope that the accepted data
in some cases will show that the received Doppler could have
been produced a second before by the receiving station
if the receiving station was also actively transmitting
at the time of reception.
The data you have is filtered and modified even further by

Craig
Markwardt


The data I have been using and sent you is the raw
values _before_ any filtering is applied by Craig.
You should get the same from your C++ program when
you extract the data directly from the NASA CD.

I am also assuming that tuning around the predicted
shift will occur
so that even if the incoming frequency is not too far

from
the predicted frequency it can still be obtained)


That is correct and an important feature of the system.

The result is another "data" file attempting to be

consistent
with the
speed of light delay.

No, the filtering removes outliers far from the mean
of their neighbours, regardless of the speed of light.


I disagree. Since this gets rid of neighbors that depart
the most from the predicted values based on the speed
of light assumptions.


Craig removes values that depart from those nearby
without comparing against predicted values so your
comments are wrong.

They are implicitly compared because most of the values are
already near the predicted values perforce.
So your comments are wrong.


It is important that he doesn't

do this since the anomaly is about +3Hz by the end
so if he filtered against the prediction he would
always throw away more high values than low, hence
he would introduce a bias into the measurement.


The anomaly is so small that the filtering does not
influence them. The problem is that the filter prevents tuning in
the true frequency produced a few seconds ago at the receiving
site by the transmitter at the receiving site.



From the telnet ephemeris I find that Pioneer 10 had the
following heliocentric,xyz, coordinates in AU units:

snip
and that the Sun at the same time had :

snip
and so Canberra in solar coordinates would have an x

coordinate
which is the negative of the sun's x coordinate here etc.

I think you must be giving geocentric, not heliocentric,
coordinates since you have no reference to the Earth or
sites in the above. That gives you a rotating reference
frame and may lead to other problems. I would suggest
using barycentric coordinates for the sites and craft
to reduce these risks.


The coordinates are what is available from telnet and since
relativistic considerations are not necessary here have no

risks

I am not using relativistic corrections anywhere except
in the Doppler formula for the conventional theory. The
risk I think is in keeping track of various parameters
and the difficulty of estimating errors. Anyway, I think
it was just a typo but an important one to correct.

If the predicted Doppler here is close to the observed

rx then
the instantaneous hypothesis is indicated.

Conversely if the actuals are closer to the conventional
prediction then your theory can be falsified.


Unfortunately because of the- acknowledged by nasa and
Markwardt


but not by you- filtering process guarantees that the
conventional
prediction is also close.


If there is a significant difference between the
predictions, they cannot both be close.

The test does not prove the conventional prediction wrong
because all frequencies not conforming to the conventional
prediction are ignored and do not become part of the available
data.
The test does indicate that the instantaneous speed of light
possible contrary to the conventional hypothesis and so in this
way proves the conventional hypothesis wrong.

I acknowledge there is filtering in the PLL which
is by far the most important from your point of view.
There is no resonant circuit at the front-end and
Craig's filtering does not use the predicted value.
I don't object to your statement in principle, I am
only correcting the details.

And I am surprised that you think radio communications can
occur without resonance


So this proves nothing about the
conventional
prediction.


It does however permit a falsification of my theory that

the
r/c speed of light does not extrapolate beyond r=c and that

the
Doppler signal could have been received within seconds or

not.

Yes, I agree. That is the reason I suggested the test and
the use of the phase shift rather than frequency directly.

However
the coseness of a single reading is a poor indicator.

But there may be hundreds of close readings just like
this
perhaps which thus confirm the hypothesis. The fact that

there
aren't
many more is because there are so many gaps in the data due

to
failed
attempts to tune in predicted frequencies ( based on the

mistaken

This is where things get a little more complicated. There
is always some error in the prediction so the receiver
must hunt around the anticipated frequency for the signal.
When the craft was close to Earth, this was done with a
wide bandwidth and once the signal was found, the bandwidth
could be reduced to reduce the noise. At greater ranges
the bandwidth must be narrowed to reduce the noise and the
search frequency moved about until the find the signal.
This is also the most likely reason why they could only
work in three-way mode recently. Better knowledge of the
frequency allowed the use of narrower bandwidth.

You are right that they would not find the signal if it
was too far off, but once found the receiver PLL locks
to the signal and the actual frequency is measured
regardless of the prediction. If that weren't the case,
the anomaly could not have been found.

and
never tested theorythat the r/c speed of light extrapolates

to
distances
greater than c.)


The problem is to obtain from NASA the correct tx

values??????

Both sites transmitted at 2110883520Hz on both days so
there is no problem with that part.


I take you at your word but would like to know what nasa
documents say this.


It is in the "ramp" records on the CD.

Where are the documents on this?

You can check
once you get the C++ program working. The values must
be multiplied by 48 to get the actual frequency. I
think Morabito and Asnar say 96 but this is obvious.

Two further pieces of information are required. First
there is a transponder ratio of 240:221 that must be
included in the predictions. Secondly Ralph, you haven't
stated the equation to be used for the speed-related
frequency shift in your theory, equivalent to Doppler
shift in conventional theory.

The Doppler shift equation is (1+v/c)f without
relativitistic
modifications which are unnecessary here where v here is the
difference
in the projections of vs an vc on the line d.


'v' is the rate of change of range, right?

(1+v/c)f is received by the spacecraft and retransmitted

as
(240/221)(1+v/c)f so that(1+ v/c)^2 times 24/221 times f

should be
received by the sending site a second or so later if the

sending
site


There are a few typos there but the formula is:

f_r = 240/221 * f_t * (1 + v/c)^2

where

f_t is the transmitted frequency
f_r is the predicted receive frequency,
v is the rate of change of range
c is 299792458m/s

Presumably v is positive for reducing range and
negative for increasing range.

was also scheduled to send at this time of reception
v denotes the sum of the projected craft and earth site
velocities
on the instantaneous line, d.
Its easy to put the data and equations in a spreadsheet

and
calculate the answer
But I would suggest using the least filtered data. I am
working on
that now


Absolutely. I will have a look at the Telnet
interface for Horizons.

best regards
George



  #9  
Old July 9th 03, 09:42 PM
external usenet poster
 
Posts: n/a
Default Spacecraft Doppler&Light Speed Extrapolation

"ralph sansbury" wrote in message ...
[snips]
I am saying that what you think was the uplink station for a
specific reception was not the uplink station. The true uplink
station was the receiving station.
If that is the case the earth would not block reception. Do
you understand?


And since the Earth *does* block reception?
Socks
  #10  
Old July 10th 03, 01:17 AM
Paul F. Dietz
external usenet poster
 
Posts: n/a
Default Spacecraft Doppler&Light Speed Extrapolation

ralph sansbury wrote:

[ incredible quantities of **** ]

Ralph, take your insanity elsewhere.

Paul

 




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