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
_______________________________________________
time-nuts mailing list -- [email protected]
To unsubscribe, go to
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.
