[time-nuts] tracking position & orientation

[jimlux]

On 11/22/19 5:04 AM, Bob kb8tq wrote:
> Hi
> 
> Indeed, I do a better job of detecting the impact of humidity ( = rainy season ) on my deck
> then I do detecting anything else on a fairly short baseline. I *do* get correct distances and
> angles between the antennas (as verified with a tape measure).
> 
> One thing you can do (with some effort) is to collect a lot of data. There is nothing magic
> about a 24 hour run. A two week run is also do-able. Lots of data will *not* take care of all
> problems. It will get the portion related to SNR down to some very small numbers.
> 
> For continental drift sort of things, find a solid chunk of rock. If it’s connected to something
> very deep, that’s best. Tie the antenna to it, possibly with a fairly short mast. Best to have a
> good view of the sky so a short mast may not be practical. In the various papers on the subject
> you see antennas on a 2’ mast mounted on tops of hills if it’s a “quick” setup.

That may only be 2 feet sticking up above the surface. There could well 
be a 10 meter deep double pipe. I can't seem to find the website now, 
but for SCIGN they had instructions on drilling a hole down to rock, 
putting a large PVC casing in, then putting a second steel pipe inside 
the large casing that actually carried the antenna, to decouple the 
surface movement effects (soil moisture making the soil expand and 
contract, for instance).

Try here: 
https://kb.unavco.org/kb/article/permanent-gnss-gps-station-planning-technology-equipment-costs-55.html

and
https://kb.unavco.org/kb/article.php?id=104