Ok, so it was a non sanctioned, unofficial competition, between 2 highly popular GNSS receivers. Anyway, I thought it might be of some interest to folks thinking about purchasing one or the other of these receivers.
I have the fully optioned BRx7 and R12 receivers, each running the latest firmware, operating on the Florida DOT FPRN network, receiving GPS/GLONASS/Galileo/BeiDou signals/corrections using Port 10000/MSM4_Near. The receivers were set up and operating side by side under low hanging, dense hardwood canopy (occasionally switching places...the BRx7 would be located on nail 1, while the R12 occupied nail 2. After several minutes the BRx7 would occupy nail 2, with the R12 on nail 1.). Corrections were coming from a FPRN base station located about 9.7 miles away.
I also run a base/rover setup with a fully optioned Leica 555 channel GS10 Ultimate/Leica GS18t Ultimate, running the latest Leica firmware, and this setup is our primary workhorse on large jobs. We just simply trust the results with this setup, and we like base/rover results/speed/confidence of shots in difficult canopy. However, I have come to prefer the BRx7 or R12 for speed while running network rovers.
Now, back to my original purpose for this thread. The short answer is that I have been unable to declare a definitive winner. For every attempt, in all but the very extreme thickest canopy I could find, both receivers (BRx7 and R12) obtained correct results. And, when 1 of the receivers was unable to get a position, the other receiver was also unable. Also, both receivers were always simultaneously seeing/using a like number of satellites (always over 20 birds).
The list price of my Trimble R12 was $27,000. The Carlson BRx7 was $12,000. Realizing how closely comparable these receivers are, my next purchase will be a BRx7 to then be able to do base/rover with Carlson's listen-listen internet correction service. Will I look to sell the R12? No. I plan to keep the R12 with me in my Rubicon at all times. For what it's worth, in my opinion they are both excellent and reliable receivers. If you got the bucks, why not get the R12? If you poor like me, get the BRx7.
How about a test between and partially blocked by metal buildings. I want that non sanctioned test please?ÿ
@jitterboogie Out here in the sticks it'd be kinda hard to find. But, if I run across such I'll do what I can.
Wow this is interesting. I am starting to look at RTK as an option in canopies.
I would like to check a couple of things.?ÿ
?ÿ
1. How do they compare to the GS18t?
2. Do you have photos on how dense the forest are?
3. Realistically how long did it take to achieve a fix in there and store a point.?ÿ
4. Are you using the BRX7 with Carlson SurvPC/SurvCE?
Understood. Warehouses and or airplane hangars is the area I'm having a hard go at times with the R12.
I LOVE my Brx-7 and am constantly amazed at the good fixes it gets in situations I would have never thought possible just 5-6 years ago.?ÿ I've checked into published control and also verified with optical gear with similar results.?ÿ ?ÿ
If you got the bucks, why not get the R12?
While I definitely agree with this statement, I would probably clarify to say "If you want the full suite of field functionality that Trimble Access gives you, and you want to be able to process all your data quickly in Trimble Business Center, and you have the bucks, why not get the R12 [R12i]?"
Differences between receiver capabilities are getting smaller and smaller. I think that software functionality/efficiency and dealer support are what make or break a manufacturer these days. Although if you are a savvy solo operator you're likely able to make most anything dance for you.
I would be curious about a base-rover test between the two, to control for any effects that the RTN might be creating.
@rover83 You hit the nail on the head.?ÿ
I started surveying on the tail-end of the era when you could pick the best instrument, data collector, etc and they would all work together.?ÿ Regardless of how we got to the proprietary world we work in, we are now in a world where it's best to a pick the color that provides the best combination of features, price, and support for you situation. There's a certain economy in having gear that just works.
@sireath 1. I have run my GS18t, with corrections coming from the Florida FPRN, in some pretty dense places, but even though you usually will be able to get the shot (and with Leica, if you get a shot it will rarely ever fail to be a correct position), it takes longer than either the BRx7 or the R12. Thus, the reason we primarily only run the GS19t with a base/rover setup.
4. SurvPC
When you compare prices, make sure you include having all the bells and whistles turned on. Those costs are often overlooked in the sales pitch. That basic $20k receiver can quickly climb if you have to pay $2500 for each constellation.?ÿ
@dmyhill (advertised prices) Fully optioned list price for R12 = $27,000, Fully optioned GS18t, about the same as R12. Fully optioned BRx7(there are no paid options) = $12,000.
I am pretty sure that the BRx7 doesnt have no calibration tilt, so is that worth 2.25 times the money?
I have used multiple units that are essentially the Carlson, and they work great.
