Any opinions on spread spec vs UHF radio? I have used both and find advantages for both. I do a lot of large tract surveying so range is important. However the spread spec seems to have less interference and issues.
> Any opinions on spread spec vs UHF radio? I have used both and find advantages for both. I do a lot of large tract surveying so range is important. However the spread spec seems to have less interference and issues.
Our Topcon 915 spreadspectrum radios are VERY limited in range. It won't allow us to even break down a section.
Yes I agree. We get about 1-1.5 miles out of our Hiper II. UHF we get 2-3 miles when it works.
I love the spread spectrum with my Leica. I use a tall base radio antenna which really helps the range. I also use an extendable pole on the rover, so if needed I can sent the rover antenna way up too.
I use the same trick. I've heard that doubling antenna height is like quadrupling the power output.
> I love the spread spectrum with my Leica. I use a tall base radio antenna which really helps the range. I also use an extendable pole on the rover, so if needed I can sent the rover antenna way up too.
Get 20' of range poles at yard sale. Or an old prism pole. UM we go up, for range.
N
We used to use a 25' level rod with the prism adapter on the top of it for the radio antenna at the base. Pound a stake on either side of the rod and clamp them all together. Never had any issues with it falling over.
UHF radios provide users with more options. You can mix different brands of UHF radios, Pacific Crest, Satel, Microhard > using the most common Modulation format: MSK modulation. UHF radios are the most common type used with RTK systems. Most all today's GNSS Smart antennas utilize internal 1 watt UHF radios. Need more Line of Sight Range? Add an external UHF Base radio to your RTK Base setup. Most of these external UHF Base radios support 10w, 25w and 35w output. All UHF radios owners/users are required by the FCC to obtain their own Radio Station license. (No > you can't use your Dealer's FCC License). FCC now requires RTK users to use Narrow Band 12.5 kHz UHF radios, effective January 1, 2013.
Are you using the correct type of UHF radio antenna with your UHF radios?
UHF radio antennas are very frequency specific. This often over looked aspect of UHF radio antennas has the biggest impact on the Line of Sight Range RTK surveyors experience. All UHF Rubber Duck Antennas are not the same.
Spread Spectrum radios can work well on project sites with high levels of RFI, or Radio Frequency Interference, like Airports, Military bases, large congested metropolitan cities. Spread Spectrum radio utilize frequency hoping technology,less susceptible to interference. Spread Spectrum, (SS) radios are very proprietary, brand specific. Cannot mix different brands of SS radios. No FCC license is required for using SS radios.
NTRIP Network RTK surveyors use cellular modems to make their data connections.
Different communication devices for various project site requirements.
-BbB B-)
That's some good information, yes we are using the original sokkia antennas that we have for two years. We have experienced loss of range and no solution-float lately. We have taken out our spread spectrum radio GPS and it works fine. I realize that the radios between the two is the only difference, so why would our Topcon be working ans seeing satellites and fixing in the other not? We have had the firmware updated and basically exhausted every possibility
About UHF, the antenna gain at the rover also makes a difference. For example in the era of 4700, 5700, the standard antenna at the rover was 5 dBi. The 5800 came with a 0.5 dBi gain. I was getting radio issues in areas where I had never experienced problems with previous models. I ended buying a SECO bracket and hot swap the 0.5 to a 5 in dead zones. Always worked good. Not too sure what's out there these days and if hot swap is still a good idea with newer radios (overload risk maybe?)
I might have problems with that in the Colorado winds. I have had tripods blown completely off the point before.