I feel dumb posting GPS questions, as I have been in management for a long time, and only recently found a way to get my hands on some of my own GPS equipment. I am currently demo'ing two used Trimble R8-2's, and trying to link/sync them with my Trimble Nomad 800 with Carlson SurvCE software.
Here's what I have been able to do:
Setup one of the R8's as a rover on INCORS, get fixed, but with HSIG and VSIG around 0.15-0.20'. These are numbers that I need to find a way to reduce, but at least I got fixed.
HOWEVER,
I went down to southern Indiana in an area with poor cell coverage and poor satellite coverage, and I couldn't get fixed. Tried for hours. The INDOT help desk said that I showed up on their map, but couldn't figure out why I couldn't get fixed.
SO,
I am trying again today to use both receivers as a Base+Rover setup. I can get connected to both individually through bluetooth connection with my Nomad, BUT I can't get fixed. I tried the same thing the other day onsite in southern Indiana after I couldn't get fixed on INCORS, to no avail. It was a wasted day. I'm getting pretty frustrated, and don't understand why I can't get fixed in a Base+Rover setup. I'm pretty sure it's a comm/setting issue, but I don't have the experience to figure it out.
Any ideas?
Thanks in advance for your input.
Regards,
Joe
BTW The position feedback I am getting is "AUTONOMOUS" with HSIG and VSIG around 3.5-4.5'.
I was able to "FLOAT" for a brief period of time at my site in southern Indiana the other day, but the HSIG and VSIG never got below 1.0'± and never got fixed.
Brother, I cannot think of any particular settings to help you with. How far south are you? Maybe I can swing by and try with my unit? Send me an email and maybe we can coordinate depending on weather and my schedule and your deadline. Good to see ya posting my old pal.
Why would you think that part of the state would have poor satellite coverage.
> Why would you think that part of the state would have poor satellite coverage.
I have experienced poor cell coverage down thar. I am guessing that Joe will simply plead inexperience regarding the satellites.
I applaud him for coming to this site for help. Sometimes it helps to wear flame resistant attire though.
> Why would you think that part of the state would have poor satellite coverage.
By that, I was referring more to the site-specific geographic challenges of being in a valley near the Wabash River (i.e. high horizon). I have heard that you can have problems getting fixed if you are not reading the same satellites as your INCORS station. On the way back, I put the receiver in the dash of my truck, and got "fixed" as soon as I got to the top of a hill a couple miles away.
I don't mind relevant, critical questions at all. Thank you for your response.
Much appreciated, Brad. Will send you an e-mail after dinner. Smoked salmon and shrimp simmered in garlic, butter, and white wine are calling...
Joe, long time lurker first-time poster. I have worked with our GPS since our first Trimble units in 1996+/-. I'm probably not as much of an expert as most of the others here on this site (and I'm hoping to stay off Kent's radar since I do a lot of RTK) but I may be closer to you than others. Our company office is here on the northside of Indy. You are welcome to email me and we can talk or even meet up to go over your settings sometime. There are a few that could affect the solution but I'm not familiar with the Nomads so I would likely need to see it in person.
Let me know.
If I understand your predicament correctly, it sounds like you weren't getting a good enough cell signal to get corrections from the internet. This would lead to an autonomous position (that's the best a receiver can do without some sort of correction). Float indicates that at one point you were getting corrections briefly, just not for a long enough period of time for the receiver to fix.
Thanks Tom. I know right where your office is 😉 and as such, it would be very helpful to meet up. E-mail me at joe@CandSSurveying.com, and i'll reply to see when we can connect...
> If I understand your predicament correctly, it sounds like you weren't getting a good enough cell signal to get corrections from the internet. This would lead to an autonomous position (that's the best a receiver can do without some sort of correction). Float indicates that at one point you were getting corrections briefly, just not for a long enough period of time for the receiver to fix.
Correct, I was not getting good enough corrections to get fixed. I assume that it was due to poor WiFi signal from my AT&T cell phone, but then when I went Base+Rover, I was also getting an autonomous position, so I'm really puzzled at this point...
sorry Joe didn't look at your profile before I posted. guess I should have looked first I'm sure you know how to contact me to
Maybe try changing the broadcast from CMR to CMR+. I think RTCM 3.0 or RTCM whatever is Topcon language. Forgive me if I have the acronyms reversed as it has been a long time since I set mine up.
BTW, I have had the same problem using topcon equipment with a Trimble broadcast system when using a VRS setup. It worked great until one of our sparsely located cors signals went offline for maintenance.
The network administrator could see me but I couldn't get a fixed position.
You might try using the single baseline option if available.
Just a thought.
> Maybe try changing the broadcast from CMR to CMR+. I think RTCM 3.0 or RTCM whatever is Topcon language. Forgive me if I have the acronyms reversed as it has been a long time since I set mine up.
>
> BTW, I have had the same problem using topcon equipment with a Trimble broadcast system when using a VRS setup. It worked great until one of our sparsely located cors signals went offline for maintenance.
>
> The network administrator could see me but I couldn't get a fixed position.
>
> You might try using the single baseline option if available.
>
> Just a thought.
Thanks for the thoughts. I was using CMR+, but this morning tried using all 4 to no avail, which is actually information that is somewhat useful (I think). I think that means it may be a radio broadcast broadcast issue (for Base+Rover setup). When I fire up the base and rover, the green radio lights are not flashing at all, which means the base is not sending corrections to the rover, which would explain why I am continuously getting an autonomous position. Now to try to figure out why the base and rover aren't communicating via the internal radios. I tried a hard reboot in case there was a setting from the previous owner, still didn't help. When I hit the "Internal Radio" configuration button, I am getting (today, not before) a "did not respond to command 7" error message. SMH...
The Nomad with Carlson can't connect to the internal radio in an R8-2. If you know anyone with a Trimble data collector ask them to check all your settings for you.
> > If I understand your predicament correctly, it sounds like you weren't getting a good enough cell signal to get corrections from the internet. This would lead to an autonomous position (that's the best a receiver can do without some sort of correction). Float indicates that at one point you were getting corrections briefly, just not for a long enough period of time for the receiver to fix.
>
> Correct, I was not getting good enough corrections to get fixed. I assume that it was due to poor WiFi signal from my AT&T cell phone, but then when I went Base+Rover, I was also getting an autonomous position, so I'm really puzzled at this point...
I didn't see anything you posted about a radio. Did you do a "here position" and then verify that the radio was "TRANS" your station information to the rover? Regardless of cell coverage, the base/rover option will work, as long as you have a radio and it's broadcasting.
Do either of the R-8's have the base code from Trimble activated?
> The Nomad with Carlson can't connect to the internal radio in an R8-2. If you know anyone with a Trimble data collector ask them to check all your settings for you.
Bingo. That did the trick. Kind of stumbled across it by accident, but up and running now, so not questioning the survey gods...
Just a quick update - sat in the parking lot monday for an hour or so with the guy who is selling me the R-8's, and managed to get it working. we went through all the frequencies and setting step by step, and neither of us is quite sure what we did right, but I am up and running. Thanks to all those who volunteered to help and offered insight.
