On Feb 29, 4:47 pm, HW@....(Dr. Henri Wilson) wrote:
On Fri, 29 Feb 2008 21:45:51 +1100, "Artful" wrote:
"Paul B. Andersen" wrote in message
...
So which "initial coarse correction after the clock is launched"
are you talking about, Henri?
If such an individual correction is done, why are then the difference
in clock rates as can be expected by clocks which are _not_ individually
corrected?

To defend Henri for an instant, it is possible he is thinking about the
original satellites, which were launched with the GR correction as remotely
settable. They were initially launched with the GR correction turned off,
and left to run like that for several days (I don't have the details here to
quote exactly) to see if the correction was actually needed (as some of
those involved doubted the GR correction was real). After that time, it was
found that the correction WAS needed, and so the synthesized clock
adjustment was turned on.

'Synthesized clock adjustments' !!!!!!!!

On NTS-2.


See how easy it is!!!!!!

Yes, we're all aware that experimental satellite NTS-2
had onboard the capability to change frequencies.

The point is, no such rate adjustment has been
included in GPS satellites since experiments with
NTS-2 verified the GPS correction, and there is no
"rate correction" done to GPS satellites because
they do not have the capability.

Instead, the adjusted frequency is hardwired at manufacture
time, before launch, and never changed.

- Randy

"Randy Poe" wrote in message
...
| On Feb 29, 4:47 pm, HW@....(Dr. Henri Wilson) wrote:
| On Fri, 29 Feb 2008 21:45:51 +1100, "Artful" wrote:
| "Paul B. Andersen" wrote in message
| ...
| So which "initial coarse correction after the clock is launched"
| are you talking about, Henri?
| If such an individual correction is done, why are then the difference
| in clock rates as can be expected by clocks which are _not_
individually
| corrected?
|
| To defend Henri for an instant, it is possible he is thinking about the
| original satellites, which were launched with the GR correction as
remotely
| settable. They were initially launched with the GR correction turned
off,
| and left to run like that for several days (I don't have the details
here to
| quote exactly) to see if the correction was actually needed (as some of
| those involved doubted the GR correction was real). After that time,
it was
| found that the correction WAS needed, and so the synthesized clock
| adjustment was turned on.
|
| 'Synthesized clock adjustments' !!!!!!!!
|
| On NTS-2.
|
|
| See how easy it is!!!!!!
|
| Yes, we're all aware that experimental satellite NTS-2
| had onboard the capability to change frequencies.
|
| The point is, no such rate adjustment has been
| included in GPS satellites since experiments with
| NTS-2 verified the GPS correction, and there is no
| "rate correction" done to GPS satellites because
| they do not have the capability.
|
| Instead, the adjusted frequency is hardwired at manufacture
| time, before launch, and never changed.
|
| - Randy

Since the GPS receiver operates on satellite time the operational
frequency is moot, but it does agree with the pendulum of the turret
clock in St. Stephen's tower.
http://tinyurl.com/357pyu

"Adding or removing a penny will change the clock's speed by 2/5th of one
second per day."
http://en.wikipedia.org/wiki/Big_Ben

"Dr. Henri Wilson" HW@.... wrote in message
news
On Fri, 29 Feb 2008 21:45:51 +1100, "Artful" wrote:

"Paul B. Andersen" wrote in message
...
So which "initial coarse correction after the clock is launched"
are you talking about, Henri?
If such an individual correction is done, why are then the difference
in clock rates as can be expected by clocks which are _not_ individually
corrected?

To defend Henri for an instant, it is possible he is thinking about the
original satellites, which were launched with the GR correction as
remotely
settable. They were initially launched with the GR correction turned off,
and left to run like that for several days (I don't have the details here
to
quote exactly) to see if the correction was actually needed (as some of
those involved doubted the GR correction was real). After that time, it
was
found that the correction WAS needed, and so the synthesized clock
adjustment was turned on.

'Synthesized clock adjustments' !!!!!!!!
See how easy it is!!!!!!

Of course it is easy .. you just use a different figure to the duration
between ticks to calculate the 'time' value. The first satellites had a
'switch 'to turn the GR correction on, and found that it was actually
necessary.

To quote from the site that Randy kindly reposted a link to:

===
At the time of launch of the first NTS-2 satellite (June 1977), which
contained the first Cesium clock to be placed in orbit, there were some who
doubted that relativistic effects were real. A frequency synthesizer was
built into the satellite clock system so that after launch, if in fact the
rate of the clock in its final orbit was that predicted by GR, then the
synthesizer could be turned on bringing the clock to the coordinate rate
necessary for operation. The atomic clock was first operated for about 20
days to measure its clock rate before turning on the synthesizer. The
frequency measured during that interval was +442.5 parts in 1012 faster than
clocks on the ground; if left uncorrected this would have resulted in timing
errors of about 38,000 nanoseconds per day. The difference between predicted
and measured values of the frequency shift was only 3.97 parts in 1012, well
within the accuracy capabilities of the orbiting clock. This then gave about
a 1% validation of the combined motional and gravitational shifts for a
clock at 4.2 earth radii.
===

Of course, for later satellites, there was no need for such a switch any
more, they could be made with the correction built-in.
Anyway.. that sounds like a possible explanation for what Henri was
saying.

Thankyou fartful, I will now be nice to you for a couple of days.

I am always fair (or at least try to be). Whether or not I agree with your
position on other things, I will treat it fairly. If I see you, or anyone
else, being unfairly criticized or misinterpreted, I will defend you on that
point. If I find I have made that mistake myself, I will apologies.

"Dr. Henri Wilson" HW@.... wrote in message
...
It is not a 'correction' as such.

It certainly looks like one.

It is merely a determination of the clock's drift wrt the GCs...so at any
GC
time the OC's reading is predictable.

So you make a correction to reduce the drift. That same amount of drift as
GR correctly predicts.

Your figures are merely departures from the expected readings.

And the departure between the corrected times and the what they should be
is within the bounds of the accuracy of the clock. if the clock were NOT
corrected, then the error would increase over time and be absolutely greater
than the errors we see.

The approximate freefall correction

What 'freefall correction' ?? If you mean the GR correction, then yes.

is pre-set in order to reduce the above
drift and minimise the error, as I explained before.

Yes .. the GR correction amount is preset to avoid the errors accumulating.

On Sat, 1 Mar 2008 10:36:41 +1100, "Artful" wrote:

"Dr. Henri Wilson" HW@.... wrote in message
news
On Fri, 29 Feb 2008 21:45:51 +1100, "Artful" wrote:


'Synthesized clock adjustments' !!!!!!!!
See how easy it is!!!!!!

Of course it is easy .. you just use a different figure to the duration
between ticks to calculate the 'time' value. The first satellites had a
'switch 'to turn the GR correction on, and found that it was actually
necessary.

To quote from the site that Randy kindly reposted a link to:

===
At the time of launch of the first NTS-2 satellite (June 1977), which
contained the first Cesium clock to be placed in orbit, there were some who
doubted that relativistic effects were real. A frequency synthesizer was
built into the satellite clock system so that after launch, if in fact the
rate of the clock in its final orbit was that predicted by GR, then the
synthesizer could be turned on bringing the clock to the coordinate rate
necessary for operation. The atomic clock was first operated for about 20
days to measure its clock rate before turning on the synthesizer. The
frequency measured during that interval was +442.5 parts in 1012 faster than
clocks on the ground; if left uncorrected this would have resulted in timing
errors of about 38,000 nanoseconds per day. The difference between predicted
and measured values of the frequency shift was only 3.97 parts in 1012, well
within the accuracy capabilities of the orbiting clock. This then gave about
a 1% validation of the combined motional and gravitational shifts for a
clock at 4.2 earth radii.

Anyone can write crap like that..knowing full well there is a willing bunch of
deluded fanatics who will believe it.




Henri Wilson. ASTC,BSc,DSc(T)
www.users.bigpond.com/hewn/index.htm

Einstein's Relativity is easy to understand if one has the IQ of a parrot and a gullibility index 0.95.

On Fri, 29 Feb 2008 13:57:08 -0800 (PST), Randy Poe
wrote:

On Feb 29, 4:47 pm, HW@....(Dr. Henri Wilson) wrote:
On Fri, 29 Feb 2008 21:45:51 +1100, "Artful" wrote:
"Paul B. Andersen" wrote in message


See how easy it is!!!!!!

Yes, we're all aware that experimental satellite NTS-2
had onboard the capability to change frequencies.

The point is, no such rate adjustment has been
included in GPS satellites since experiments with
NTS-2 verified the GPS correction, and there is no
"rate correction" done to GPS satellites because
they do not have the capability.

Instead, the adjusted frequency is hardwired at manufacture
time, before launch, and never changed.

That's of no importance.

The clock can run at any rate as long as it's a known one.
A simple conversion is carried out at the receiver.

- Randy



Henri Wilson. ASTC,BSc,DSc(T)
www.users.bigpond.com/hewn/index.htm

Einstein's Relativity is easy to understand if one has the IQ of a parrot and a gullibility index 0.95.

"Dr. Henri Wilson" HW@.... wrote in message
...
On Sat, 1 Mar 2008 10:36:41 +1100, "Artful" wrote:

"Dr. Henri Wilson" HW@.... wrote in message
news
On Fri, 29 Feb 2008 21:45:51 +1100, "Artful" wrote:


'Synthesized clock adjustments' !!!!!!!!
See how easy it is!!!!!!

Of course it is easy .. you just use a different figure to the duration
between ticks to calculate the 'time' value. The first satellites had a
'switch 'to turn the GR correction on, and found that it was actually
necessary.

To quote from the site that Randy kindly reposted a link to:

===
At the time of launch of the first NTS-2 satellite (June 1977), which
contained the first Cesium clock to be placed in orbit, there were some
who
doubted that relativistic effects were real. A frequency synthesizer was
built into the satellite clock system so that after launch, if in fact the
rate of the clock in its final orbit was that predicted by GR, then the
synthesizer could be turned on bringing the clock to the coordinate rate
necessary for operation. The atomic clock was first operated for about 20
days to measure its clock rate before turning on the synthesizer. The
frequency measured during that interval was +442.5 parts in 1012 faster
than
clocks on the ground; if left uncorrected this would have resulted in
timing
errors of about 38,000 nanoseconds per day. The difference between
predicted
and measured values of the frequency shift was only 3.97 parts in 1012,
well
within the accuracy capabilities of the orbiting clock. This then gave
about
a 1% validation of the combined motional and gravitational shifts for a
clock at 4.2 earth radii.

Anyone can write crap like that..knowing full well there is a willing
bunch of
deluded fanatics who will believe it.

You still in denial I see.

"Dr. Henri Wilson" HW@.... wrote in message
...
On Fri, 29 Feb 2008 13:57:08 -0800 (PST), Randy Poe

wrote:

On Feb 29, 4:47 pm, HW@....(Dr. Henri Wilson) wrote:
On Fri, 29 Feb 2008 21:45:51 +1100, "Artful" wrote:
"Paul B. Andersen" wrote in message


See how easy it is!!!!!!

Yes, we're all aware that experimental satellite NTS-2
had onboard the capability to change frequencies.

The point is, no such rate adjustment has been
included in GPS satellites since experiments with
NTS-2 verified the GPS correction, and there is no
"rate correction" done to GPS satellites because
they do not have the capability.

Instead, the adjusted frequency is hardwired at manufacture
time, before launch, and never changed.

That's of no importance.

The clock can run at any rate as long as it's a known one.
A simple conversion is carried out at the receiver.

How will the receiver know how much to correct by if you don't know what the
rate is?

Dr. Henri Wilson skrev:
On Fri, 29 Feb 2008 10:49:44 +0100, "Paul B. Andersen"
wrote:

Dr. Henri Wilson wrote:
On Thu, 28 Feb 2008 12:28:20 +0100, "Paul B. Andersen"
wrote:

Dr. Henri Wilson wrote:
On Wed, 27 Feb 2008 12:17:30 +0100, "Paul B. Andersen"
wrote:


Paul, you keep repeating the same irrelevant numbers.
Quite.
The "irrelevant numbers" showing that:
- The average rate error is -2.29E-12, which is
0.5% of the GR correction.
- Since the differences in the rates of the clocks are
as can be expected from the precision of the clocks,
it is clear that no individual correction is made
of the rate of the clocks after launch.
- Since all the clocks are corrected by the same GR-correction
before launch, and the rates after launch are correct within
the precision of the clocks, it proven that the GR correction
is correct within the precision of the clocks.

But if you keep calling the actual measured data
"irrelevant", maybe the data will go away?
Because you can make a wrong assertion right by
repeating it often enough, can't you?

The main software adjustment is made immediately after launch.
YOUR figures show daily clock drift over and above the main correction.
Give it up, Henri.
Even you can see that the "irrelevant numbers" show that
no such "software adjustment" of the rate is done "immediately after launch".
You ignore the initial coarse correction after the clock is launched.
Is too, is too! eh?
You are a bit slow, are you not?

1. All the clocks are built equal. They are all manufactured according
to the specification which says that they shall run slow by
delta_f/f = -4.4647E-10 relative to the SI-definition of a second.
The "Interface Control Document":
http://www.navcen.uscg.gov/pubs/gps/...d200cw1234.pdf
From section 3.3.1.1:
"The SV [space vehicle] carrier frequency and clock rates --
as they would appear to an observer located in the SV --
are offset to compensate for relativistic effects. The clock
rates are offset by delta_f/f = -4.4647E-10, equivalent to
a change in the P-code chipping rate of 10.23 MHz offset by
a delta_f = -4.5674E-3 Hz. This is equal to 10.22999999543 MHz."
So when the clocks come from the manufacturer they will all run at
the same rate, but for the inherent limited presicion, which is in
the order of few parts in 10^12. That means that the rate of the clocks
can be expected to differ by a few parts in 10^12. The rate of each clock
may change a little with time, but mostly will the clocks that are running
a little too fast continue to do so, while those that are running too slow
will continue to do so.
-------------------------------------------------------------
When the clocks are not individually adjusted, their rates
can be expected to differ by few parts in 10^12.
------------------------------------------------

Is there anything in the above you don't understand?

2. Actual measurements of the clocks in orbit show that their
30 days average rate errors (compared to GPS-time) we
PRN Rate error
x10-12
1 -2.51
2 -3.05
3 -5.31
4 -17.15
5 -14.99
8 1.53
9 -1.81
10 11.40
11 0.02
12 0.79
13 -2.17
14 -3.29
15 2.49
16 -0.15
17 0.67
18 -3.00
19 -1.47
20 0.76
21 0.76
22 -0.53
23 -2.85
24 -3.02
25 -5.04
26 -10.15
27 -2.61
28 0.54
29 -6.11
30 -1.49
31 1.42

As you can see are the rate differences as can be expected
by clocks which are not individually adjusted.

Is there anything in the above you don't understand?


So which "initial coarse correction after the clock is launched"
are you talking about, Henri?
If such an individual correction is done, why are then the difference
in clock rates as can be expected by clocks which are _not_ individually
corrected?

It is not a 'correction' as such.

It is merely a determination of the clock's drift wrt the GCs...so at any GC
time the OC's reading is predictable.

So no corrections as such is made of the rate of clocks after launch.

OK, I accept the retraction of your claim:
"Of course the bloody rate is changed after launch."

Your figures are merely departures from the expected readings.

Departures from the _correct_ readings, yes.

The approximate freefall correction is pre-set in order to reduce the above
drift and minimise the error, as I explained before.

Come again?
To "reduce the above drift"? :-)

So are you saying that what you call "The approximate freefall correction",
namely THIS correction:
1. All the clocks are built equal. They are all manufactured according
to the specification which says that they shall run slow by
delta_f/f = -4.4647E-10 relative to the SI-definition of a second.
The "Interface Control Document":
http://www.navcen.uscg.gov/pubs/gps/...d200cw1234.pdf
From section 3.3.1.1:
"The SV [space vehicle] carrier frequency and clock rates --
as they would appear to an observer located in the SV --
are offset to compensate for relativistic effects. The clock
rates are offset by delta_f/f = -4.4647E-10, equivalent to
a change in the P-code chipping rate of 10.23 MHz offset by
a delta_f = -4.5674E-3 Hz. This is equal to 10.22999999543 MHz."

Is to reduce the drift of the clocks shown below?

2. Actual measurements of the clocks in orbit show that their
30 days average rate errors (compared to GPS-time) we
PRN Rate error
x10-12
1 -2.51
2 -3.05
3 -5.31
4 -17.15
5 -14.99
8 1.53
9 -1.81
10 11.40
11 0.02
12 0.79
13 -2.17
14 -3.29
15 2.49
16 -0.15
17 0.67
18 -3.00
19 -1.47
20 0.76
21 0.76
22 -0.53
23 -2.85
24 -3.02
25 -5.04
26 -10.15
27 -2.61
28 0.54
29 -6.11
30 -1.49
31 1.42

You _are_ confused, are you not? :-)
Or rather - you are saying stupidities because you don't know what else to say.


But you have finally accepted that no correction
of the rate of the clocks are made after launch.

So we can sum it up:
1. Prior to launch, the clocks are adjusted by -4.4647E-10 as predicted by GR.
(You are free to call this adjustment with a precision equivalent to
14 significant digits "the approximate free fall adjustment" if you like.
A silly name, of course, but the name doesn't change the reality.)
2. No individual correction of the rate of the SV-clocks is made after launch.
3. Actual measurements of the rate of clocks in orbit show that the errors
in the rate is as can be expected by the precision of the clocks,
which is less than 1% of the GR-correction.

The inevitable conclusion is:
The GR-prediction of the rate of clocks in GPS-orbit is proven to
be correct within the precision of the clocks.



--
Paul

http://home.c2i.net/pb_andersen/

On Sun, 2 Mar 2008 21:39:15 +1100, "Artful" wrote:

"Dr. Henri Wilson" HW@.... wrote in message
.. .
On Fri, 29 Feb 2008 13:57:08 -0800 (PST), Randy Poe

wrote:

On Feb 29, 4:47 pm, HW@....(Dr. Henri Wilson) wrote:
On Fri, 29 Feb 2008 21:45:51 +1100, "Artful" wrote:
"Paul B. Andersen" wrote in message


See how easy it is!!!!!!

Yes, we're all aware that experimental satellite NTS-2
had onboard the capability to change frequencies.

The point is, no such rate adjustment has been
included in GPS satellites since experiments with
NTS-2 verified the GPS correction, and there is no
"rate correction" done to GPS satellites because
they do not have the capability.

Instead, the adjusted frequency is hardwired at manufacture
time, before launch, and never changed.

That's of no importance.

The clock can run at any rate as long as it's a known one.
A simple conversion is carried out at the receiver.

How will the receiver know how much to correct by if you don't know what the
rate is?

plonk


Henri Wilson. ASTC,BSc,DSc(T)
www.users.bigpond.com/hewn/index.htm

Einstein's Relativity is easy to understand if one has the IQ of a parrot and a gullibility index 0.95.