Given the L-band requires the $500/year subscription, would I be better off using two Facet standards (as base/rover), or can I expect the subscription service to come down in price as more subscribers are signed on? Tough choice as I hate subscriptions especially when I would only infrequently use the service.
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Sounds too expensive. 
It’s a tricky call. I would say this: if you’re going to be located in a certain 10km area, setup a fixed base using an ESP32 with a ZED breakout: https://learn.sparkfun.com/tutorials/ho … p-option-2 It’s cheaper than a 2nd Facet, and very precise (14mm). If you’re doing work all over a county or larger area, L-Band is really convienient.
Facet L-Band Pros:
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Super easy to setup/use. No NTRIP configuration.
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Reception anywhere in US48/EU.
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No cost or hassle of setting up a base
Cons:
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Not quite as good RTK Fix precision (~3cm vs 1.4cm)
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Subscription cost = $500 yearly
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Limited to US48/EU
Two years later: With the release of the Torch, I am leaning towards getting that and using the Facet L-Band as a Base and the Torch as a Rover (both without the Correction Service). The challenge will be to get the Facet acting as a Base to properly log data formatted for OPUS positional correction. Overall, cost-wise, A standard Facet ($700) and the Torch ($1500) is cheaper than using the Facet L-Band with $600 yearly subscription (and likey to go up every year as it has) after one year.
Curious, it’s now February 2025, what did you decide to do? My need and configuration will be different, probably Torch with just the $6.00 a month (Six dollar) a month subscription to decrypt the satellite correction broadcast. I am only using this on my farm, so most of the time I won’t need the $6 subscription. Everyone’s use case is different but I am trying to learn from everyone’s use case. Thanks
Use an RTK postcard and quad band antenna for cheaper and can make a base with Lora antennas for sub 1k for rover/base, radios, and antennas
@ChrisO , just a clarification here : the Torch Point Perfect Subscription requires an Internet connection (usually cell phone). The Torch is not decrypting the Inmarsat signal on “L-Band”.
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Oh, I thought that the two different Point Perfect subscription prices (Torch $8 a month vs Facet L-Band $60 a month) was due to what type of correction. e.g. Cheap for them to give you a monthly decrypt code for a satellite broadcast over sending data over an internet subscription, or maybe that cost is reversed. Or is the $8 for Torch an introduction rate and then it becomes $600 a year for Torch too?
One key note - on my property there is ZERO Verizon coverage but I do get 1-2 bars of AT&T service, so if the Torch needs Verizon it’s a no go. In the hills and valleys of Tennessee, you can go from No AT&T to NO Verizon, to some of both, one, then the other…
$8 Torch Correction Service LINK RTK Torch Registration and Renewal
$600 Facet Point Perfect LINK PointPerfect Renewal
Sorry for all the questions, but it’s just not clear to me what all the costs of these units really are. on-going. I promise if I buy either the Facet, Facet L-Band, or the Torch, I will write up a post from my NEWBIE perspective so others starting from almost negative knowledge (What I thought I knew was wrong) won’t ask such simple questions.
And I did some ChatGPT and Google Searches for options for perhaps the standard FACET and NTRIP, and … TopNET Live one service provider… leaves me out in the cold as I am just a few miles from Sweetwater TN… too funny, looking into Prosumer Survey equipment seemed like it wouldn’t be so hard Ha!!!
@ChrisO , RtkDirect has a station that must be your neighbor.
I don’t have any experience with the site.
One thing to keep in mind is RTK corrections have nowhere near the bandwidth requirements as Voice Communications.
At 1Hz, a triple-system correction stream takes about five times less than a voice call with the lowest bitrate codec. However, service prioritization may vary. But another advantage is that 100% correction stream integrity isn’t even needed.
I haven’t pulled the trigger yet for two reasons. I discovered the Torch does NOT have the same built in radio as the LORA standalone radios needed for the Facet. So the Torch/Facet for Rover/Base isn’t really viable. Also, accuracy testing of Facet over the summer yielded less than needed performance (foot results vs inches needed) using the available CORS network around central NH. This has led me to considering using the newest Reference Station offering to set up my own CORS station. I haven’t nailed down this approach yet. For me, subsciptions only make sense for something that will be only very short term. Otherwise a fully owned solution usually proves far more reliable.
Just use 2 postcards and loras
The other thing you gain is quad band at a reasonable price point. I have a facet and even with our good RTN that was accurate within 0.06’. The postcard does even better.
Was that 1ft accuracy with Facet (not Facet LBand) using RTK or no corrections just pure satellite?
I continue my comparison, of the Facet L-band, the Facet No Lband, and the Torch for my needs on my farm. I’d love centimeter accuracy, but in reality, +/- 1 foot would be totally acceptable, but… well I am a farmer geek so I’d be willing to spend some money to improve accuracy, but I am not going to be using this every day. I’d use it for a week or two, then it will sit for months. Then use it for a couple days, then sit until the winter and leaves are down… I am not putting it on a tractor or robot tiller.
I can get AT&T service on my farm in 90% of the valleys, but ZERO Verizon any where.
I am reading every post to learn what people like and dislike from the 3 options. 4th option being self-build with that “Postcard” like @AORPLS posted, but I don’t know all the parts needed so shying away from that as I am a technical farmer, not an electrical engineer with a farm.
I made an ID for myself so I can investigate further. The best I could tell by zooming in was this is only 5-10 miles at most from my farm. The map for some reason doesn’t label all the roads so had to make so … guesses. If I get a Torch or Facet, and experiment with this I will put more information in my “Beginners outline”
This looks like an interesting option. I’ll look into it further.
@AORPLS , could you list all the parts to build? I’d even be interested in which mounting post/tripod you used. I am starting from zero knowledge. I will probably still go pre-build like Facet or Torch, but maybe my Radio Shack experience in high school would allow me to build this. And what RTK service did you use and cost? Thanks in advance if you have time to outline the details. – Chris
Specifically, I used a Facet L-Band device without the L-band corrections (the subscription had expired). I set up over a known Geodedic marker and logged data for 24 hours. I then used both the OPUS and CSRS-PPP (Canada) to get corrections. I struggled with OPUS but eventually got repeatable and reliable corrections thanks to a number of Sparkfun contributers. Anyway, reviewng my results more closely now, I was getting final results to 1-3" accuracy after 2-3 days of setup/processing time. Accuracy was within feet for a 3 hour setup and fast solution. I put the project on pause at that point since I was busy and haven’t re-visited it. I did not like that it would take days to get a base station setup to an accuracy within inches. I had low confidence in my results because of how frought with error the whole process was as a beginner and the overall poor CORS solutions due to lack of covereage here in NH. However, that confidence increased as familiarity with the process was gained. I haven’t had the opportunity to pick up where I left off at this point. But the challenge for me is that I survey different locations in locales where phone service can be non-existent or spotty. However, I am usually on site for a couple of days and the goal would be to set up an accurately located base station. That way I should be able to get overall satisfactory x,y,z data for a local survey using a rover. I was considering the Reference Station approach as an alternative CORS solution for those times when phone/internet reception was available. My reluctance was born out of the lack of confidence in the accuracy of results I was able to achieve with my Facet based experiments. And like I said much of that was with overcoming the learning curve of the GNSS technology and not necessiarily the Facet equipment. Edit: I originally purchased the Facet L-band for a number of reasons, but primarily because it was the lowest cost solution (when it was first released) and gave accurate results to 3-feet +/- which was all the accuracy I needed when delineating wetlands. However, for topo surveying that accuracy is not acceptable which is why I am looking for repeatable 1" accuracy now.
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So we have ORGN here in Oregon we are spoiled it’s free and uses 3 cors averaged I have seen 0.04’ checking into benchmarks horizontally. I am a professional land surveyor but also used to play around with gps on tractors and farms.
The postcard and antenna and portability shield and battery were like 375 so x2 if you want base rover and the Lora kit is 175 so sub 1k all together. I am happy to solder and ship you stuff as I have nice tools for doing so. I also have the printer files for the cases thanks to Steven from sparkfun
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