The latest next big thing in Ky road construction seems to be the R-turn, or J-turn intersection. Where a 2 lane road intersects a 4-lane with a median, instead of going straight across, in order to avoid driver side impact collisions, the 2 lane crossing traffic has to turn right onto the existing slow lane, ?ÿcross into a new left turn lane 1000?? or so down the 4 lane to a new U-turn crossover, then proceed across to a new right turn lane on the right side back to the crossroad. We are retrofitting several into existing conditions, and new design plans already have them. I guess studies show they reduce fatalities, so we??ll see.?ÿ
I had the following issue on one we have just started. There were 3 original control points on the project. We use Trimble construction GPS on equipment and grade checking. I use Access and a Trimble R-10-2 upgraded to the R-12 on the Ky VRS network. So I went out, added a couple of control points using total station to cover the site, calibrated to the 5 control points, and set a base pole by the R/W fence for them to set their base on. Done it a hundred times, ?ÿNever had a problem, until now. Usually whatever base they are going to use is tied ?ÿup someplace else and doesnt get to a job until they are ready to start it, thats why I use mine to get ahead of them. So they bring out the base, I plug in the base location, Get their rover going, head to check a control point, suddenly no satellites. Thinking its the antenna or a cable, swap those out, still nothing. Sitech guy brings out a new base setup, still no satellites. Hooks his rover up to VRS, no satellites. Set my R10 back on it, ?ÿ20 satellites. WTF.?ÿ
So I set another base 1000?? up the road, 23 satellites on mine. Set various bases on it, try rovers, no satellites. Sitech updates firmware in bases and finally one of them starts getting 20 satellites. But none of the rovers would get more than 6 satellites. When it would briefly fix, could check into a control point and it was right on the money, but wouldnt maintain a fix. No radio.?ÿ
There is a state police post across the road. Trimbles best guess is that they have something in there radio system thats interfering with the ability of the construction stuff to receive satellites or radio, but it doesnt affect my R10. Havent had any issues like this before, but have an airport job starting Monday and Trimble warned me the same thing may happen there.?ÿ
?ÿComments?
By golly, Ol' Grandpappy never had that problem when he was surveying.?ÿ Sometimes chains and chaining pins start to look good again.
If you are talking of Continuous Flow Intersections, we have built one project here with it and the city has done another intersection that seems to have helped a bit.?ÿ Time will tell how effective it will be.
https://www.virginiadot.org/newsroom/hampton_roads/2018/virginias_first_continuous_flow131405.asp
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The second project has that where you go through the intersection, make a u turn and then turn right on to a slip lane to the secondary road.
One time had a mapping thing, mostly scanning, need to get some items, wide open (in a grape vineyard).
Can't get RTK to work at all.?ÿ Seems to me we had satellites, just couldn't get the radio link to work.?ÿ Tried everything I know, couldn't get it to work.
Fortunately the thing was small enough that I set up the S7 as low as possible and took shots under the grape plants (too high to conveniently get over).?ÿ Didn't affect the robot radio at all.
Found out later there is a high powered wifi transmitter on top of the hill above us.?ÿ It totally stepped on every RTK channel.
We have worked at airports and Emergency Command Centers (lots of radio gear) with no issues.
Another time, at an accident investigation in an active fire area.?ÿ We had done other work on the fire but miles away with no problems.
Day 1 set up RTK base fairly low in a bowl, do a bunch of RTK surveying below the spur ridges, no problem.?ÿ Next day set base up high to get over ridge to other side.?ÿ Nothing, can't get it to work, pulling my hair out, WT actual you know what??ÿ Finally move the base back to first location, go back to try to get shot on control point up high, nope nothing, can't fix.?ÿ HMMMM.?ÿ Finally between me and partner we say lets go over there behind hill and see what happens, works great no problem.?ÿ Did a faststatic on the control point we needed.?ÿ the GNSS part wasn't the problem, had that, it is the data link radio that is getting stepped on.?ÿ Never did figure it out except we think some fire people must've had something transmitting down in the next valley over.?ÿ Had no problem as long as the terrain shadowed it, whatever it was.
A radio scanner to listen and see if your radio channel is active before turning your gear on could be a very useful tool. Some are under $100.
It's been rare, but I have experienced interference like that.
There was a very enthusiastic ham radio operator somewhere in Karnes County, TX, when I was working in the oil patch. Whenever this guy fired up his system (complete with 80+ foot tall antenna mast) our crews couldn't work within a couple miles of his house. We had to go knock on his door and ask if he wouldn't mind shutting down while we staked a few pads...
The construction stuff is (typically) in the 900 MHz range, while the survey-grade gear is 450 MHz. Wouldn't surprise me if the police radio band was closer to one or the other.
(Edit to add: Bill has the right idea, a scanner is extremely useful when operating in areas with possible interference. Technically, according to the FCC, we are supposed to be checking frequencies before we start work to ensure we are not stepping on anyone else.)
most puzzling part was how mine would pick up all the satellites using vrs and theirs wouldnt pick up any using vrs. I wouldnt think the radio would have anything to do with that. I was using a mifi, he was using his phone. And the fact that the base or rover wouldnt pick up any satellites.?ÿ
Don't know if this will help, but it's an interesting site anyway. ?????ÿ
I used to do a ton of work in the cellular industry and would encounter similar issues from elements on the tower being surveyed. You are probably in the "blast field" of a microwave dish the police station is using for communications, they operate right around 300MHZ.?ÿ
Police radio wouldn't be operating at 300 MHz, which falls in the 225 MHz ?? 400 MHz military aircraft band. In the US, police land mobile radios have traditionally been in the 150 MHz ?? 162 MHz and 450 MHz ?? 470 MHz bands, and, for some years now, more and more have been moving to the 851 MHz ?? 869 MHz band. There's still some rural or statewide police use of frequencies down around 40 MHz. None of these frequencies are what I consider microwaves ?? that term is usually used for frequencies from about 3 GHz to about 30 GHz (3,000 MHz to 30,000 MHz).
@bill93 Mark Silver of iGage provides a small hand held radio with each sale for just that purpose. It's so rural where I am I never used it but I can see the value of it after reading this thread!
Here's one that has been built here in Austin at Slaughter Ln and MoPac (Loop 1 that isn't a loop). Time will also tell how effective it is but so far, I think it's working.?ÿ
There's another one at the SW edge of Austin, near Oak Hill, that is "interesting" to drive through. I see the logic and the intent but it's a weird thing to gaze upon.
The diverging diamond interchange works but it is not continuous flow.
@holy-cow They built one of these at the I-40/Hwy 66 interchange that leads to Pidgeon Forge and Gatlinburg.?ÿ ?ÿThe backups to get from Hwy 66 onto I-40 were legendary but after the change backups are almost non-existent.
I have gone through the one on I-44 at Rangeline Road in Joplin, MO a few times.?ÿ Seemed to work fine but would reserve judgement to those who need to pass through there every day.
