On 2014-12-14 10:29, Francesco Messineo wrote:
On Sun, Dec 14, 2014 at 6:12 PM, Bob Camp kb...@n1k.org wrote:
that's not meant as a time nut stratum 1.
It's just a free gps module I would like to recycle as a needed
stratum 1 server for a small network.
Of course if I can find informations on
Hello, all
I have a couple of GPSDOs (KS, z3805a) hooked up to a fixed outdoor antenna
through an HP 58516 splitter. I notice that when I powercycle the GPSDOs
(which I generally try to avoid), the position they come up with differs
from time to time in at least the last three digits (and height
olep...@gmail.com said:
My question is twofold; 1) is this for some reason a bad idea? And 2) How do
I average the numbers? I can not put my finger on it but it feels wrong to
average lat, long and height independently.
It seems like an interesting idea to me.
It would be interesting to run
I am new to this list and to this topic, but it seems to me that if one
wants to come up with an average of a set of spatial measurements, one
would use distance as the parameter to be averaged. The distance would
presumably be that from a fixed spatial reference point (0,0,0). One
would then
I would recommend determining your terrain's elevation using a topo map and
estimating or measuring antennas height above ground. And then excluding
survey results with wacko altitudes before averaging.
While we often set the elevation angle mask high for timing purposes, for
survey purposes
Hi
If you treat it as a sine, you certainly get further. There are some neat sine
wave input chips. The next layer to the problem is that the trapezoid may be
slower than (or faster than ) a sine wave depending on just what’s going on
with the system. That will make it a bit difficult to know
On Dec 15, 2014, at 2:27 AM, Mike Monett timen...@binsamp.e4ward.com wrote:
Hi
On Dec 10, 2014, at 11:12 PM, Mike Monett
timen...@binsamp.e4ward.com wrote:
[...]
Can you tell me some of the ones that do?
I have yet to see one for under $2K that does it correctly. I
don't have
On Mon, Dec 15, 2014 at 9:09 AM, Brian Inglis
brian.ing...@systematicsw.ab.ca wrote:
On 2014-12-14 10:29, Francesco Messineo wrote:
The A1029, which is a newer model, has indeed a PPS output and I've
been able to find a datasheet for it but the pinout isn't anything
like the A1025.
I planned
The Ublox M8N can send out raw measurements with messages TRK-MEAS and
TRK-SFRBX for observation and navigation data: you can postprocess
them to improve the accuracy.
http://www.rtklib.com/rtklib_support.htm
On Mon, Dec 15, 2014 at 12:43 PM, Tim Shoppa tsho...@gmail.com wrote:
I would recommend
On Mon, Dec 15, 2014 at 10:52 AM, Azelio Boriani azelio.bori...@gmail.com
wrote:
The Ublox M8N can send out raw measurements with messages TRK-MEAS and
TRK-SFRBX for observation and navigation data: you can postprocess
them to improve the accuracy.
And searching the archives for rtklib
Users of my web site may have had difficulties getting some of the files in
the last couple of months. Particularly, those files that were recently
uploaded.
Typical symptom would be a file that was uploaded, was removed from the
Recent Upload folder (indicating that I moved the file to it's
Take a look at the code in Lady Heather that does a 48 hour precision survey.
It calculates a weighted median position of fixes over 1 hour periods then
calculates a final position from those medians. The algorithm was developed by
having people around the world with Thunderbolts and quality
I reply to myself,
On Mon, Dec 15, 2014 at 2:41 PM, Francesco Messineo
francesco.messi...@gmail.com wrote:
I've found a couple of articles saying the A1025 indeed has PPS output
as I suspected. However, none of them reports any hint about the
pinout of this module.
The module itself is
Hi
Simple answer - there is no simple answer.
You will get significantly better results by intelligently processing the data
than by a giant “average everything in sight” approach.
Also consider that various GPS modules seem to have offsets in their nav
solution. The NIST papers on various
On Mon, 15 Dec 2014 17:55:20 -0500, you wrote:
Hi
Simple answer - there is no simple answer.
You will get significantly better results by intelligently processing the data
than by a giant average everything in sight approach.
Also consider that various GPS modules seem to have offsets in
Hi
On Dec 15, 2014, at 6:39 PM, Angus not.ag...@btinternet.com wrote:
On Mon, 15 Dec 2014 17:55:20 -0500, you wrote:
Hi
Simple answer - there is no simple answer.
You will get significantly better results by intelligently processing the
data than by a giant average everything in
This may be one of those cases where the human brain's ability to see
patterns would help to see the distribution and eliminate outliers. Plot
a manageable set of X and Y points, and another set of X and Z points.
To make the three dimensions plot as one in a statistical distribution
(bell)
Hi
On Dec 15, 2014, at 7:19 PM, Bill Hawkins b...@iaxs.net wrote:
This may be one of those cases where the human brain's ability to see
patterns would help to see the distribution and eliminate outliers. Plot
a manageable set of X and Y points, and another set of X and Z points.
yup
Hi
Actually there may be a Time Nuts relevant reason for wanting to know the true
/ correct / survey location.
If your desire is to know UTC to ns or something like that, an indicated
position error *probably* relates directly to a time error. Being able to
correct the position error may
kb...@n1k.org said:
The problem shows up when the GPS constellation is in a configuration that
accentuates the error. Thatâs often a 12 / 24 / 48 hour sort of thing.
It would be interesting to compare the results from daytime vs nighttime, or
today vs yesterday.
--
These are my opinions.
Hi
On Dec 15, 2014, at 8:07 PM, Hal Murray hmur...@megapathdsl.net wrote:
kb...@n1k.org said:
The problem shows up when the GPS constellation is in a configuration that
accentuates the error. That’s often a 12 / 24 / 48 hour sort of thing.
It would be interesting to compare the
On Mon, Dec 15, 2014 at 6:39 PM, Angus not.ag...@btinternet.com wrote:
But is it the closest to the 'true' position that you really want, or
the best estimate of where the particular GPS you are testing thinks
it is?
I don't understand what you're saying here. Can you phrase it differently?
Hi
Here’s another way to sort this all out:
For ADEV, you probably want to get down to ~ 1x10^-13 at 1 second. If the
system improves by 1/tau, it will be adequate for anything else you want to do.
It’s a system that would need to resolve 100 fs, so most of the “counter”
devices that die out
Hi
On Dec 15, 2014, at 8:29 PM, Paul tic-...@bodosom.net wrote:
On Mon, Dec 15, 2014 at 6:39 PM, Angus not.ag...@btinternet.com wrote:
But is it the closest to the 'true' position that you really want, or
the best estimate of where the particular GPS you are testing thinks
it is?
I
With all the discussion about surveys position accuracy, I have a question
about my choke ring antenna. There is an arrow marked N on the underside
of the rings. How accurately does the alignment need to be to North?
True north or magnetic north (my thinking says True North)?
Does the
On 12/15/14, 5:35 PM, Bob Camp wrote:
Hi
On Dec 15, 2014, at 8:29 PM, Paul tic-...@bodosom.net wrote:
On Mon, Dec 15, 2014 at 6:39 PM, Angus not.ag...@btinternet.com wrote:
But is it the closest to the 'true' position that you really want, or
the best estimate of where the particular GPS
Hi
If:
1) You are doing a survey of a number of points in an area
2) You want to hit the “1/5 mm accuracy” that your system is rated to :)
3) You really do care
Then:
You point the arrow north to the best of your ability to make all the antenna
errors show up in the same direction. It
On 12/15/14, 5:46 PM, Dave M wrote:
With all the discussion about surveys position accuracy, I have a question
about my choke ring antenna. There is an arrow marked N on the underside
of the rings. How accurately does the alignment need to be to North?
True north or magnetic north (my
On Mon, Dec 15, 2014 at 8:35 PM, Bob Camp kb...@n1k.org wrote:
So the question - If they are not going to be equal, which one do you pick?
The better one. If the math is sound the presumably the better position
results in better time.
If there are correlated defects then I suppose the GPS
On Mon, Dec 15, 2014 at 9:01 PM, Jim Lux jim...@earthlink.net wrote:
if you've got observables and they're in RINEX format, you can do offline
processing through JPL's GIPSY thing..
According to the upload form APPS still requires dual frequency. The
underlying Gipsy system may not have that
On 12/15/14, 6:46 PM, Paul wrote:
On Mon, Dec 15, 2014 at 9:01 PM, Jim Lux jim...@earthlink.net wrote:
if you've got observables and they're in RINEX format, you can do offline
processing through JPL's GIPSY thing..
According to the upload form APPS still requires dual frequency. The
With all the discussion about surveys position accuracy, I have a question
about my choke ring antenna. There is an arrow marked N on the underside
of the rings. How accurately does the alignment need to be to North?
True north or magnetic north (my thinking says True North)?
Does the
Jim Lux wrote:
On 12/15/14, 5:46 PM, Dave M wrote:
With all the discussion about surveys position accuracy, I have a
question about my choke ring antenna. There is an arrow marked N
on the underside of the rings. How accurately does the alignment
need to be to North? True north or magnetic
Hi,
I think the answer is probably no, but is there a sanctioned
way of coercing the fine Lady into unusual comm port settings?
For instance, can I get her to do: 9600, 8, Odd, 1 without
resorting to the whip?
Thanks!
-Chuck Harris
___
time-nuts
Hi,
I think the answer is probably no, but is there a sanctioned
way of coercing the fine Lady into unusual comm port settings?
For instance, can I get her to do: 9600, 8, Odd, 1 without
resorting to handcuffs, and the whip?
Thanks!
-Chuck Harris
35 matches
Mail list logo
