It is true that you can input text like on a cellphone, check out this:
next time you have selected to input text to fill in a box, look in the corner of the screen for a red icon, tapping it should pull up an onscreen keyboard.
Bryan
It sounds like you really need some GPS Bryan with all those hills and such. If I worked all the times in areas like you have described I would have got some units a long time ago.
Dave's a great guy, and he knows GPS that's a fact! I hope this works out for you Bryan.
Steve
> You have mentioned this "fried" set of RTK receivers before, but I don't recall any details (brand/color, problem, cause). I may have missed it though (I do that a lot).
From old RPLS.com posts, Steve's system is/was a Javad demo sold by our local Topcon dealer. I don't know what caused the mishap -- I'm not sure Steve knows, either -- but apparently it requires replacement of expensive innards to repair, so it remains unrepaired.
Bryan
> Gee Bryan..I am racking my brain to try and remember when I shot a distance over 2200 feet, and that was last weekend on a drizzly day and basically flat ground.
>
> LA County has so much control in the ground I think it has lowered the basin a few inches.
And the important other element to keep in mind is that GPS simply will not work in Los Angeles County. There really isn't any point to even thinking about the ways in which GPS could improve your work significantly because you will be in Los Angeles County where, as we all know, GPS will not work.
No, the best thing to do it never, ever to even think about using GPS. Sure those other surveyors who don't survey in Los Angeles County can get away with using GPS. And, sure, you probably could use it to improve your own surveys considerably, but it ... would ... just ... not .... be .... right. The only clearly ethical course is obviously to advise all prospective clients who may call that GPS will not work in Los Angeles County, so not to ask about it.
30-45 Minutes For 0.01' Horizontal
> I don't accept less. L1 is a bit more dependant on lots of satellites and constellation positions since it cannot fully account for atmospheric conditions.
>
For short baselines, and 1,200 feet (365 meters) certainly qualifies as a short baseline, the atmospheric conditions cancel out in the double difference processing. See: http://www.plazio.net/GPS/Carrier%20Phase%20Observables.htm for a fuller explanation.
Peter Lazio
30-45 Minutes For 0.01' Horizontal
Peter
My understanding is that the iono can only be removed by double differencing but that it requires L1/L2 and not just L1 alone.
Have I been mistaken all these years?
Deral
But at 1200' then you would not be concerned with the iono anyway. I only worry about it over 3km.
Kent
Why do you keep saying that GPS will not work in the Los Angeles area?
It does Kent..it really does.
30-45 Minutes For 0.01' Horizontal
> Peter
>
> My understanding is that the iono can only be removed by double differencing but that it requires L1/L2 and not just L1 alone.
>
> Have I been mistaken all these years?
>
Yes and no.
The definition of a short baseline is one where the ionosphere cancels. If the baselines are short enough the ionospheric component of the undifferenced observations at both stations are the same or very nearly so. When forming the double difference observable the double difference tropospheric and ionospheric terms cancels or nearly so.
For longer baselines, observing L1 and L2 allows for the computation of the ionospheric component.
Peter Lazio
Steve
Topcon has no idea either. One day it worked and the next day both were "fried". I've asked them many times what would cause that and they can't tell me.
Steve
Since we're beating a dead horse anyway, what model receivers were they? I've heard that the Hipers use the same USB connector for the power and download ports, and that plugging the power cable into the download port will cook the main board. Could this be a similar issue?
Jim
i don't remember the model off the top of my head. There is/was only one way to attach any of the cables, they all had different connectors, although I suppose there's always some way a crew person could have hooked something up wrong and was afraid to tell me. That's what I wish Topcon could have told me is what you would have to do to the setup to fry it that bad besides having it struck by lightning.
Steve
I don't think the USB lemo will go into the power lemo on the hiper or vice versa. They look the same but have a different number of pins if memory serves me correctly. I don't have them with me right now because I don't need them this week.
I have a Hiper XT on which the USB no longer works and I was told by Topcon that it would take a new main board to fix. Fortunately the receiver works but the download is through the serial port which is slow.
If I was spending a lot of dollars on dual frequency receivers I would go with Trimble because they seem to have better long term durability. The Topcons may be slightly cheaper but they are known to have catastrophic failures, not good when you spend 10s of thousands of dollars and expected to get your money back not by using them every day for 2 years but occasionally for 10 or 15 years.