Usually I do RTK over cellular, and really only use UHF radio for very short range. I have Trimble R10-2 and Trimble R10 receivers with internal radios, which can be set at 0.5w and 2w. I also have a TDL450 which has 0.1w, 0.5w, 1w, 2w, and 4w that I use with Alloy receivers. Also a Trimmark 3.
I have a project coming up with 8 remote fly-in sites with no cell service, so I will need to use the UHF radios. It should be line of sight from the base locations at each airfield, in other words nothing blocking the signal. Distances range up to 2 miles.
My question is how far do the internal radios typically go? I do have one external antenna (i.e. connects to the antenna port and can be elevated) for the R10 and also for the TDL 450. I would prefer not to have to use the 450L or the Trimmark 3 due to power issues (need an extra battery). Fallback is RTX, which I have but I am not sure how well it will work in high latitudes (61°N) since the corrections come from a geosynchronous satellite above the equator.
Power is one consideration, but what is the gain on the UHF antenna you are using?
As long as you are using a properly tuned antenna, you can get different results.
I think we have 0db gain and 5db gain for UHF base/rover and switch depending on the use case.
See the diagram below.
*EDIT: There was an application for PC called PCC Range Estimator (by Pacific Crest) that seems to have disappeared.
Lately it seems that Trimble has really scrubbed the internet for all the old stuff that was a great resource for "legacy" application(s).
And log data at the base & rover for post processing...?!
The 2 watt radio in the R10 will easily handle 2 miles line of sight. A lithium cow-bell battery will last two maybe three days. If the 450 is needed then you don't need to have a car battery unless you blast it out at 25 watts. I would take it and only use it when you lose signal if you ever do (two lightweight cow-bells and one charger).
The Trimble shop here tells me a half mile for every watt so 2 watt = 1 mile. I've found the 2 watt internals usually reach a little over that-- maybe 1.5 miles, but I'm in some pretty flat country.
Unfortunately I don't live in a flat area to test it out. Very hilly here. But I think we will have line of sight so should be good.
I don't think I can depend on RTX...here is their official coverage map. But last year a rep from Trimble said MAYBE I could get RTX up there, and that a Zephyr 3 has a higher gain for RTX than an R10-2.
Can you pack a 5m pole, cable and 1m aerial? I find that makes a bigger difference to range than the watts you are pushing out. And looking for the highest point in the area to put your base on.
Don't forget your Canadian radio license!
I have averaged close to 2 miles with R10 and R12’s. That is some pretty tough areas. That’s just the internal radios. Please though take a few extra antennas. Those things seem to be hit or miss on durability. We got a batch of bad ones and were having serious issues. But once we worked through that we were golden. A friend here in VA averages 1 mile around rural boundaries so lots of trees and hills in between. I can’t remember now exactly how we ended up configuring them but we changed some settings and it helped a lot with range.
Mountain top to mountain top, I once got 18,000 feet on a 1 watt internal radio on a Javad T-3 but that is the exception. Got a 6,000 footer once but generally in my region its a half a mile or so.
Something we have done a few times in mountains is I would set up 2 bases a few miles a part. Same frequency same everything just know the different station index number settings in survey style. One would be delayed so not to walk on each other. We did this as points in valleys or other side of mountain face would not allow signal from 1 but swapping to other and we could get that one. Where we could get both was nice as we could position the new point from two different ones as we navigated the 18 mile stretch. We did have a few photo points that I could literally walk 5 ft and get signal and then for the point I couldn’t. Just terrain. I was able to add an extra section to the rover rod and get it that was right at 2 miles. So I think if you have good line of sight a good battery at base you should be getting close to 2 miles. Set up the base to log data in worst case scenarios and then log some data at rover and post process in those sticky situations. Good luck. Watch the glide slopes path on airstrips. Sometimes years ago this would knock out signal period . I always had a cowbell yellow brick at base so i didn’t have to return for battery. Or a good car battery with cable.
At a rail yard got 4 miles with external antenna on R10 base. Might have been some rail cars in the way too. So 2 miles at an air strip should be easy.
I sat on a point yesterday, I had line of sight for what I needed which was 1.7 miles from the base to a little road survey 1 mile away. I had the repeater but didn't need it and that was with a .5 watt R8.
With a 2 watt R10 we seldom need the repeater. Those things will go 4 miles line of sight.
