In a jam and need help, uhf problem or something else?

Jim Campi

Active Member
Gentlemen,

I haven't posted in a while. Things have working fine with one exception. I can no longer obtain a fixed signal.

Several months ago, using my LS and T2 on UHF with a 1-watt radio I could not obtain a UHF connection even over very short base lengths (50 ft line of sight). I have been using the typical set up of the base radio on the typical flexible antennae. The LS would instruct to add external antennae. I would add the antennae and the system has been working ok. The external antennae connector on the LS loosened up a few months ago and I have been carefully connecting the external antennae with care not to rotate connector (fear of damaging the internal wire by over torquing).

Now I am getting a UHF connection of 100 percent (as usual); however, no fixed solutions. Tapping on on the UHF icon on the home screen and reviewing the radio properties I see that the sysem has a connection signal strength in the -70s dB range. I also see data that are both received and lost.

I know there is something wrong with the internal LS antennae. The external antennae has the loose connector and has been working fine up to this week. As far as I know this is the only problem with LS.

The LS has between 15 and 21 satalites in view. When I switch to the T2 it has 6 satelites in view (combination of GPS and GLONSS). The mask on the T2 is either 5 or 10 degrees.

I really need to finish a few surveys and can then send the unit in for service.

Does this sound like it's a UHF connection problem? If not, does anyone have any advice on what is preventing a fixed solution. I am working on a 5-7 acre parcel in the unincorporated county. Few overhead obstructions. The landform shape of this site is valley. I have setup my base both on the valley floor and ridge. My expectation is 6 fixed engines that where the system will just "want to run". Instead, the system will not fix. As a last resort I adjusted some of the constellation and satelite settings under the advanced settings page. Not sure if this did much. I believe it's back at the original settings.
 

John Thompson

Well-Known Member
I also see data that are both received and lost.
Are a bunch of the packets lost or just a few?
When I switch to the T2 it has 6 satelites in view
I'm guessing too few base satellites is preventing a fixed solution. Did you try clearing NVRAM and updating firmware in the T2?

Are you able to move to a site with cell service and test if you can get a fixed solution by sending corrections via TCP instead of UHF?
 

Jim Campi

Active Member
The packets lost are about 10 percent...

I was thinking too few satellites in view could be an issue. What didn't make sense it that it also does not work at my home office and I typically work in the area of my survey and there are not issues with transmitting base connections.

I do have a cell and uhf radio on my LS. Do I need a static IP. I could connect the T2 via a cellular phone or jet pack so they both will communicate over TCP/IP. I can also probably connect via wifi near my office. Do you know if there are instructions floating around to configure TCP/IP? This will work for testing and also most but not all of my sites in general.

When possible do you find it better to use TCP/IP rather than UHF?

I also have not tried picking up a position via cors. This will potentially rule out the LS. I normally only use the CORS when it's absolutely.
 

Matthew D. Sibole

Well-Known Member
5PLS
When I hear things like this the first question I have is have you updated to Linux?

If you can turn things on and connect to remote assistance so someone can take a look it would be very helpful.

What you are saying does not sound like a uhf problem but I would need to see it to be sure.
 

Jim Campi

Active Member
When I hear things like this the first question I have is have you updated to Linux?

If you can turn things on and connect to remote assistance so someone can take a look it would be very helpful.

What you are saying does not sound like a uhf problem but I would need to see it to be sure.
Hi Matt,

Yes I upgraded quite some time ago. I will connect later today and post here when setup.
 

John Thompson

Well-Known Member
10% lost packets sounds high to me. Seems like I've seen an occasional packet lost here and there, but I haven't paid it much attention.
Do I need a static IP.
Yes, unless you want to try the method described in this thread. I haven't tried it.
Do you know if there are instructions floating around to configure TCP/IP?
Matt Johnson posted some instructions here a long time ago. These may be out of date and incomplete, though. I suggest you get help from Adam or John Evers in setting it up.
When possible do you find it better to use TCP/IP rather than UHF?
Most definitely.
 

Shawn Billings - Javad

Active Member
JAVAD GNSS
Sounds like multiple issues.

The Triumph-2 should be tracking more than 6 sv's in a good location. As John said, clear the NVRAM on the Triumph-2.

10% lost packets is very high. It might not be a problem if the number isn't growing and there is some explanation initially for the lost packets, but generally I cannot explain this except for there being a hardware issue.

-70db reception from a 1-watt radio would be acceptable at several hundred feet from the base. At about 100 feet, you should be seeing around -35db with the external antenna. -70 is still within operational range though.

The BER (Bit Error Rate) will also tell you if those messages are being understood.

Start with the Triumph-2 tracking. You can't RTK with poor data from the base.
 
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