CDF and solution issues

[Bruce Dawson]

I am beginning to wonder if I have a problem with my LS. Yesterday morning around 10 or so I was working in a relatively open area. A high ridge about half a mile to the west and 2000 feet above me, but lots of open sky to the south, north and east. No real trees. I kept getting "CDF" in the Solution Mode area and it would set there for perhaps 5 minutes. No Data coming through when I looked. Then suddenly I would start getting solutions, which would last for maybe two shots, then back to CDF. I ended up just quitting for a while, doing sewer dips then tried again perhaps an hour later and things seemed better. Not perfect, but better. Here are some screen shots of what I was seeing:

I actually don't recall ever seeing "CDF" until this last update. Is this a clue that I have issues with my LS?

Thanks for any help!

Bruce

 

[Shawn Billings]

It means that the LS is solving a position without corrections (standalone using SBAS). It could be in the LS or it could be the corrections that are being sent. I see that the radio strength in the screen capture looks good, but the question is whether the base is sending good data. Also whether the LS is correctly reading the data coming through.

 

[Adam]

I'd check the setup, advanced, rtk, and make sure upsampling is checked on and set to .2. I notice yours says 2/0 meaning 2 hz in and 0 hz out. Or set it to no upsampling and 1 hz and see if the corrections come thru better. What's your base?

 

[Bruce Dawson]

Here is my RTK setup. Base is a T2.

 

[Shawn Billings]

Not sure why you are at 0.5 instead of 0.2 but that isn't related to your issue. Running at 0.2 will get you 5Hz while 0.5 will get you 2Hz. It will make a slight improvement in performance under canopy running at 5Hz.

Can you verify that your base was started with good coordinates (2D delta and Delta H are green)? There should be a screen capture of the base/rover setup screen stored with the base point that you can check this by. A bad base coordinate will cause this situation.

If that's not the problem, I'd try clearing the NVRAM on your base. You can do this through base rover setup by selecting the panel below start/stop base (shows the base name and rover name).

 

[Bruce Dawson]

Shawn, here is my setup screen shot:

Base point was good, I checked into several other points to verify. I will change the RTK Rate to 0.2. Had the same issue yesterday on a point or two, again having to wait several minutes for the CDF to be replaced by good solutions. I also cleared out the T2 NVRAM a couple weeks ago but will look at it again.

 

[Shawn Billings]

Change transmit to one second period and modulation to DQPSK. Upsampling makes a 1 second correction into 2Hz or 5Hz.

 

[Bruce Dawson]

Okay Shawn, I cleared out the NVRAM again and also updated the firmware (it was due). I changed to one second broadcast and modulation to DQPSK.

I will give this a try and see what happens.

Thanks!

 

[Shawn Billings]

Ok. I can't put my finger on any one of those being the issue, but let's see how it works now. Let us know.

 

[Bruce Dawson]

Did a small staking job on Monday and Wednesday, things went great. No issues. I think you guys may have fixed my problem.

Thanks again!

Bruce