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Base station ufh radios
Posted by jawja on November 15, 2017 at 8:08 pmSo, can someone teach me some on base/rover radios. As general rule, how do they work, what kind of distance do they get, etc.
I have done static, I have done VRN, I have even done omnistar. Just never did base/rover.
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shelby-h-griggs-pls replied 6 years, 5 months ago 13 Members · 20 Replies- 20 Replies
The Base Radio is the Transmitter. The Rover Radio is the Receiver. The Base Radio is usually from 2 watts of transmitting power to 35 watts of transmitting power. You need an FCC license to operate the Base Radio. The Base Radio and the Rover Radio have to be set to the same Frequency’s. FCC assigns you frequencies you can use. A 2 watt Base Radio will reach out around 2 miles under ideal conditions. A 35 watts radio used as a Base Radio can reach out 6 miles under ideal conditions. Most 35 watts radios can function as a repeater giving you a couple more miles of range. The 2 watt Base Radio operates off your GPS batteries. A 35 watts Base radio operates off a separate battery. Lots of different opinions on which battery is the best. A 35 watts Base Radio creates some heat and needs to be mounted in an open area for vinalation. It needs a mast mounted antenna. Most radio problems are caused by lack of adequate power to the base. Always make sure your Rover is receiving the Base radio before you take off surveying. There you have RTK radio 101. Any questions?
We use Topcon Hiper V base/rover and they get 1.5 to 2.5 miles under most conditions. They can function in wide band as well as narrow band. We also use them with a TDL-450 external radios when necessary. Keep in mind that just because a radio can broadcast at 35 watts, that doesn’t mean that wattage will get you the most distance. We run ours at 8 watts. it seems to be a good compromise of distance, heat, and battery life. I’ve heard of the TDL-450 can be configured to run in wide band which allows the entire system to function much smoother. I would never suggest that one run their radios in wide band because that is not legal, but it is an option. 😉
Skeeter1996, post: 455813, member: 9224 wrote: The Base Radio is the Transmitter. The Rover Radio is the Receiver. The Base Radio is usually from 2 watts of transmitting power to 35 watts of transmitting power. You need an FCC license to operate the Base Radio. The Base Radio and the Rover Radio have to be set to the same Frequency’s. FCC assigns you frequencies you can use. A 2 watt Base Radio will reach out around 2 miles under ideal conditions. A 35 watts radio used as a Base Radio can reach out 6 miles under ideal conditions. Most 35 watts radios can function as a repeater giving you a couple more miles of range. The 2 watt Base Radio operates off your GPS batteries. A 35 watts Base radio operates off a separate battery. Lots of different opinions on which battery is the best. A 35 watts Base Radio creates some heat and needs to be mounted in an open area for vinalation. It needs a mast mounted antenna. Most radio problems are caused by lack of adequate power to the base. Always make sure your Rover is receiving the Base radio before you take off surveying. There you have RTK radio 101. Any questions?
Actually, that explains a lot. Thanks for the primer.
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Radio power (wattage) and range have a logarithmic relationship – you have to increase the power tenfold to effectively double the range. So operating a TDL450 at 35 watts is not necessarily the most beneficial; as has been noted, they use a lot more battery power and they have a problem with excessive heat. We run ours at 16 or 25 watts. You also want to make sure you’re sending the smallest packet available (CMRx rather than CMR+, in the case of Trimble) at the fastest baud rate that is feasible (generally 8000bps with Trimble using narrowband radios, although 9600 is possible).
UHF radios are effectively line of sight dependent. You’ll lose range if there is a lot of ground clutter, and will not get reception if the signal is totally obstructed. Pine woods will knock down a UHF radio about as fast as anything. The best single thing you can do to increase your range (legally, anyhow) is boost the height of your transmitting antenna.
There have been several posts on here about batteries; you want a battery that is made for the constant loading and daily charge / discharge cycle. We use batteries that are made for Hoveround chairs and they have virtually eliminated our once frequent battery problems.
One more trick for Trimble users..
I take the antenna from the 450 box and plug it into the r8. I use a long cable and run it up 10 plus feet. We get well over 2 miles in pine covered mountains. Use a cowbell battery and it runs dawn to dusk with ease.To add. Height and locaton of antenna is far more important than power. Choosing a good base location and putting that antenna as high up as you can will trump higher power exponentially.
In my experience more watts = more penetration not range. I can turn watts down in fields and open and get just as far as 35 watts but pine trees knock it out quick.
I concur that antenna height and free path are critical factors for range.
In free space 4 times the power will double distance, D~sqrt (power), but in a complicated environment that’s optimistic.
.With all radios regadless of frequency, a directional antenna rather than omni directional will do wonders as long as you are working in the direction of the gain. Proably most critical aspect of gaining range and most often overlooked.
SHG
Jawja, post: 455821, member: 12766 wrote: Actually, that explains a lot. Thanks for the primer.
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Well now you get more information than you would imagine.
thebionicman, post: 455906, member: 8136 wrote: One more trick for Trimble users..
I take the antenna from the 450 box and plug it into the r8. I use a long cable and run it up 10 plus feet. We get well over 2 miles in pine covered mountains. Use a cowbell battery and it runs dawn to dusk with ease.” Use a cowbell battery…”
What is a cowbell battery? The cowbells I know are powered by the cows themselves… (Perhaps HC will want to weigh in on this)
We started using the cowbell with the chicken bucket.
Antenna height is everything. We have a 30?? tall mast we put our base antenna on. It makes a huge difference.
The rubber duck antennas on the rover don??t work very well. They work fine up close or in the wide open but be have seen double the distance using an external antenna on the rover. It doesn??t have to be tall either they make a bracket that clamps on to your rover rod and you can put a little antenna that is less than a foot tall on it and it makes a huge difference.
We recently surveyed around 2500 points on a six square mile area with lots of hills and thick thick thick trees with a single base location and no repeaters and 16 watts on the base. Set your base up in the highest location possible and get the antenna in the air. I have seen radio signals blocked a distances of less than half mile when there is a hill between you and the base.
Drilldo,
That’s some good advice.
NateDrilldo, post: 456357, member: 8604 wrote: Antenna height is everything. We have a 30?? tall mast we put our base antenna on. It makes a huge difference.
The rubber duck antennas on the rover don??t work very well. They work fine up close or in the wide open but be have seen double the distance using an external antenna on the rover. It doesn??t have to be tall either they make a bracket that clamps on to your rover rod and you can put a little antenna that is less than a foot tall on it and it makes a huge difference.
We recently surveyed around 2500 points on a six square mile area with lots of hills and thick thick thick trees with a single base location and no repeaters and 16 watts on the base. Set your base up in the highest location possible and get the antenna in the air. I have seen radio signals blocked a distances of less than half mile when there is a hill between you and the base.
Only problem is you can’t do that with an R10. I use to do it all the time with my 5800.
Sure you can. You just need a SMA connector on the antenna cable instead of a TNC.
Drilldo, post: 456508, member: 8604 wrote: Sure you can. You just need a SMA connector on the antenna cable instead of a TNC.
But then I can’t use it with my trimarks and 450.
You would likely want separate cables anyway. The antenna cables I use with my base radios are longer. I have a 6′ one I use for small jobs when the antenna is on a tripod and a 30′ one when I put it up in the air.The antenna cable on the rover is only 1-2′ long as you don’t want to have a ton of cable up there getting tangled up in everything.
- Posted by: Skeeter1996
Drilldo, post: 456357, member: 8604 wrote: Antenna height is everything. We have a 30?? tall mast we put our base antenna on. It makes a huge difference.
The rubber duck antennas on the rover don??t work very well. They work fine up close or in the wide open but be have seen double the distance using an external antenna on the rover. It doesn??t have to be tall either they make a bracket that clamps on to your rover rod and you can put a little antenna that is less than a foot tall on it and it makes a huge difference.
We recently surveyed around 2500 points on a six square mile area with lots of hills and thick thick thick trees with a single base location and no repeaters and 16 watts on the base. Set your base up in the highest location possible and get the antenna in the air. I have seen radio signals blocked a distances of less than half mile when there is a hill between you and the base.
Only problem is you can’t do that with an R10. I use to do it all the time with my 5800.
And that is one reason for still offering a model of receiver without everything in the box, or at least allow for an external antenna connection for both the comms and the GNSS signals, plenty of applications are much more suited to separating the components.
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