Nate's Suggestions for choosing a RTK BASE Site.
Best is 100% sky view. On a tall hill. The highest for miles.
Take your inclinometer, and stand there, and spin in a circle, looking at 10å¡ UP. This is my mask angle. I am looking for objects obstructing, above 10å¡. If you have to have a tree there, let it be an oak. Not Deciduous (Pine). If you have to have a tree, let it be in the northern 140å¡, and let it be as small of an obstruction as possible.
NO metal barn roofs, near the base.
Not a good idea to set it near enough the highway, for occasional multipath, from passing trucks.
Not a good idea to set it across the road from a cafe. I saw one set that way, and an 18 wheeler parked beside it, (maybe the driver was eating lunch) This is leaving yourself vulnerable.
I hear alot about RTK is not accurate.... but not alot about procedure. Your rover can have wide open sky, but the BASE be by a bridge, and you can be multipathing the base all day long. Talk about dithering things!
I saw one the other day, set up for machine control. It had the BASE set on a GPS tripod. It was one of those special ones, that maintain the HI at 2 meters, and have 3 legs, where the pole can slide through the quasi tribrach. It was leaning at about 10å¡, sideways. And, the grader was going furiously. It was near a sign, that gave it a load of multi-path. There were lath around the point. Probably a control point. Somebody's gonna get the blame.
N
All good suggestions. I'll add one more. If you make so a thief will have to get out of his vehicle and walk even 50 feet the chance of your base getting stolen drop dramatically.
I would also add try to stay out from under power lines.
I heard a trainer - might have been Mike McInnis, I don't remember - explain it best. He said think of your overall error budget as filling a bucket - if the bucket overflows, you've exceeded your budget. And if you fill the bucket 3/4 full at the base, that doesn't leave much for the rover. You want the conditions at the base to be as close to ideal as possible.
Agree with Lee. Any challenges at the rover will affect the position at the rover for that one shot. Any challenges at the base will affect every shot at the rover.
Nate, You have to explain this one to me, "If you have to have a tree there, let it be an oak. Not Deciduous (Pine)"
As far as I know Oak's are deciduous and pines are coniferous. I would rather try to get a shot through pine needles than leaves, but would avoid both.
Dtp
Hey Foggy! Brain fart. Best explanation I know.
Nate The Surveyor, post: 337723, member: 291 wrote: Hey Foggy! Brain fart. Best explanation I know.
Been there myself, I was just wondering 🙂 Thanks Nate "the brain farter" LOL
From what I've been told pine trees are a bigger problem primarily because of the higher moisture content, but I would think the density of the cover is probably a factor as well. All I know for sure is that pine forest is the worst place to try to use RTK; the radio doesn't penetrate it either.
I set my base in the shade so the paint doesn't fade...
I have seen the old satellite dishes, that were covered with a screen like mesh, with the actual antenna being on a pod, at the middle. The dish acted as a reflector, to concentrate the signal, at the antenna. This method is alot how pine needles affect rtk as well. Except, it does not concentrate it. It scatters it. Pines don't make a very good parabolic reflector, to concentrate the signal!
Could be because the Oaks drop their leaves for part of the year. Also, the leaves are somewhat smaller with some more space between them on these southern oaks than on the northern ones.
thebionicman, post: 337736, member: 8136 wrote: I set my base in the shade so the paint doesn't fade...
I use to that with my resections. Why not be comfortable while running the gun. Jp
Sounds like JOBO.....:angel:
What ever happened to jobo
http://edwardsmemorial.com/fh/obituaries/obituary.cfm?o_id=2368714&fh_id=10429&apos ;">He passed away a couple years ago.
Jobo was awesome.