Here is a step by step method for understanding how to choose the best antenna for your hotspot placement. Each placement demands a well matched antenna in order to provide value to the Helium Network and consequently earn the most HNT possible for that location. Do NOT, by the way, try to get the giant antenna in the picture below. While it looks huge and cool and rad, it is the wrong antenna to use for these deployments. I spent a fair amount of blood and treasure to learn that lesson. You don’t need to.
First: Hotspot placement optimization is FAR more important than what antenna you use, more on that here.
Second, for those of you who just want AN ANSWER: Simple: Pick up one of these if you’re on a budget (use code GRISTLEKING to knock off another 5%), get this if have plenty to spend or choose from the McGill selection. They’ll all work well.
Put it outdoors at least 10′ above all the buildings around you. Run 40′ or less of LMR400 cable to it from your hotspot. If you have to go more than 40′, use LMR600 if you’re feeling extravagant. That’ll probably get you 80% of the results you could get with far more effort and expertise.
Wait, you want to actually learn and match your antenna to your situation so you get the maximum rewards possible?
Ok, let’s start with broad strokes: The antenna you choose for your hotspot placement should match your topography, your elevation, and your lines of sight.
Let’s start with topography. Topography refers to the buildings, earth, and water that surround, channel, and block your radio signals (propagation.) The topic of radio propagation involves a tremendously deep dive all the way down to the fundamentals of physics, but we’ll keep it pretty simple.
BLUF (Bottom Line Up Front) – The flatter your topography AND the more trees/vegetation you have blocking your Line of Sight to other hotspots, the higher gain antenna you can use, up to 9 dbi.
Remember, topography isn’t just hills and mountains, it includes buildings, trees, and other obstacles.
Ok, let’s get dirty! In general, earth in the form of mountains or hills will block radio signals. Even though a hotspot may seem very close to you, if there’s a hill between the two of you, you probably won’t witness each other.
You may check out your location on the Helium Explorer Coverage map and think you’re perfectly positioned in regards to nearby hotspots, like this:
Remember to check Google Earth!
See how that spot is tucked into a bunch of hills? Unless you put up an antenna that’ll stick over the top of the hills, you’re restricted to witnessing only other hotspots in your immediate area, and in this case, that area is small!
One of the best tools to use when assessing a new site is HeliumVision. Remember, location is FAR more important than antennas. If you’d like to learn more about HeliumVision (I use it in every one of my consults) I’ve built a Master Class on it, over here.
Ok, so that’s earth. Earth = No Radio Waves Getting Through.
What about buildings? How much will buildings block or reduce the power of radio propagation?
According to a study done in 2012 on a wide swath of building materials and focusing on the GSM 900 MHz band, a reinforced concrete wall that is 20cm / ~8″ thick will attenuate the signal by 27 dB. An interior plaster wall will reduce power by anywhere from .8 to 3 dB.
What does that mean? Disclaimer: RF geeks, I’ma get loose with terms here. Relax.
This reduction in power is called “attenuation.” In general with radio communications, you don’t want any attenuation. Attenuation can happen with earth, buildings, forests, and even window coatings. How much power will you lose? Let’s run some numbers.
American based hotspots start off by pushing out 27 dBm. European and other areas start WAY lower, at 14. Add the gain (dBi) from your antenna and subtract the losses from any connections to figure out your Effective Isotropic Radiated Power (EIRP).
That means a 6 dBi antenna will give you 33 dBm of EIRP with a US hotspot. 27dBm + 6dBi = 33dBm in the direction of antenna gain. Now you’ve got to calculate cable and connection loss.
As a rough rule of thumb, each connection (hotspot to antenna cable, antenna cable to antenna, or going through an enclosure wall using a connector) will drop your EIRP by .5 dB. Cable losses vary by cable, which is why most people use a “low loss” cable like LMR400. If you want to run your EIRP numbers, here’s how.
Ok, ok, ok, why does it matter whether or not you know your EIRP?
Let’s take a short detour into dBm and power. dBm is based on a logarithmic scale. For every increase of 3 dBm, there is twice as much power output. Every increase of 10 dBm has a tenfold increase in power. The difference between a 3 dBi antenna (what most hotspots ship with) and an aftermarket 9 dBi antenna is a factor of 4!
Of course, that 4x power comes at a cost; the beam is focused; more laser and less lightbulb. That means that unless you aim your antenna very carefully, you can blast all that power into places that have no hotspots.
Here is a great example demonstrating attenuation and topography. This hotspot is placed on the north side inside a building. It’s up high with a higher gain antenna, and in general, inaccurately aimed over most of the nearby hotspots.
Most of the witnesses it’s getting are further north. Some of the signals bounce off to the side, proving that “RF is weird.”
To the south, the signals are blocked or attenuated by interior and exterior walls, but apparently there is a small window or opening where those weakened signals are escaping, then going pretty far over the water. Pretty neat, right? I mean, not for the hotspot owner, but it’s a neat demonstration of the concept.
That image is also a great example of why you should never put a hotspot antenna inside; you are losing a ton of power before the radio waves ever get outside the building.
Water allows radio signals to travel much further than normal; look at any hotspot next to a body of water and you’ll see it will connect with other hotspots at much further ranges across the water than it will across land.
Let’s not get too into the weeds here. As I said at the beginning, the general rule for topography is this: The flatter your topography, the higher gain antenna you can use, up to 9 dBi for 95% of placements. Beyond 9 the pattern generally gets too precise to provide the Wide coverage (the W in WUPU) that we want.
Remember, topography includes not just hills, mountains, and water, but all the buildings, bridges, and other structures that might block your radio signal. Cities in general do not have a flat topography, even if they’re built on flat land. All those spiky buildings sticking out will gobble up your radio signals.
That brings us to ELEVATION. If you want to bend your mind a little bit, think about this: The higher your elevation, the flatter the relative topography is, and the LOWER dbi antenna you can use. Wait, what?
Remember, a high dbi antenna focuses the signal of your antenna. In an omni antenna (we’ll get to directional or sector antennas in a minute), that shape becomes a flatter and flatter plane. If that plane is super flat, it’ll fly right over the tops of all those hotspots you want to hit. Let’s go through 3 examples.
Now, those aren’t how it *actually* works. The gain patterns are nowhere near as different, and a high gain antenna will STILL hit the ground within 1,000′ of even a 100′ building. Still, you can see why in *most* cases, you want a low or medium gain antenna up high.
You can also run that idea backwards; if you’re in a really flat area where you don’t have a lot of obstacles, a high gain antenna might be your best bet. Still, most people don’t live in the desert, and the flattest state in America has a ton of trees on it. If that’s your scenario, get a high gain (6-9 dBi) antenna up over the tops of those trees for maximum coverage.
That brings us in a roundabout way to Lines of Sight. Remember that $39 paper I quoted earlier regarding how much RF energy a given building material would absorb? The general takeaway for us Helium Hotspot owners is this: Our antennas won’t blast through much more than 2 buildings.
That means if you’re INSIDE the building, you’ve burned most of the energy of the antenna just getting outside the walls. If it hits just one more “thing”, whether it’s a building, a tree, or a billboard, that’s probably the end of the line.
This “Lines of Sight” idea has an important implication in understanding how some of the top earning hotspot/antenna combos are doing so well. The hotspot Docile Bone Pony* (when this was written, one of the highest earners in the world) is on top of a 16 story building in a major city with a medium/high gain antenna (8 dbi from eBay on 60′ of LMR400.) It has Lines of Sight to a lot of other hotspots, BUT those other hotspots don’t have great lines of sight to other hotspots around ’em.
That means that DBP is seeing a lot of hotspots that AREN’T seeing a lot of hotspots. I’m going to anthropomorphize this a bit, but their only option is to communicate with DBP. So they do. And DBP earns like crazy. It’s an example of the incredible earning potential that exists when providing asymmetric value to the network.
While we’re on Lines of Sight, let’s talk about the range of a standard hotspot. According to some excellent work done by the inimitable @para1 on Discord, most hotspots do most of their witnessing within a 10km range. Now, an in depth discussion of the implications and restrictions of this table is beyond the scope of this article, but your general takeaway should be “Optimize your antenna for hotpots within 10 km” aka most people don’t need a high gain antenna.
I’ll double tap this range thing with an example of a hotspot I run, which has a 3 dBi HNTenna on top of a 20′ pole on top of a ~30′ building. It *routinely* gets witnesses over 200km away. While it seems that a high gain antenna will get you better range, it doesn’t really matter. It’s Line of Sight that is the secret here.
Finally, Lines of Sight can be blocked by forests. Depending on who you listen to, LoRa doesn’t go through much more than 60 meters of dense forest. I’m sorry rural Florida, you’ve just got a tough row to hoe on that one. Dense forest in between you and other antennas is about the only time a higher gain (up to 9 dBi) makes sense, and even then it may not make a giant difference. Forests are RF sinks.
There is one more thing to think about with Lines of Sight. The 900 MHz frequency needs some runway, ideally 50’/15m to fan out enough to diffract around obstacles. Read that again and you’ll have an advantage over everyone who doesn’t get that concept.
The concept of Fresnel zones and diffraction in radio wave communication is one of the fundamental drivers of the “RF is weird” refrain you’ll hear whenever you see a pattern that doesn’t immediately make sense. Basically, the further out your radio waves go, the more they can spread out along their radiation pattern, the less likely that all of the waves get blocked, and the more likely that at least some of ’em will get to another hotspot.
At some distance they’re so spread out that you’re basically not going to make a connection, so the effective “window” shrinks back down. Like this:
If you set up your antenna so that you’ve got lots of clear space around it before it hits obstacles, those radios waves have enough spread to start “bending around” those obstacles. This is yet another reason not to set up inside.
Here’s another “I definitely didn’t go to art school” drawing to demonstrate the idea of runway and diffraction.
If you give those radio waves some room to spread out, they can get around obstacles. Let ’em breathe!
Ok, we’ve got one more thing to consider before wrapping up. Many of you will have been scouring ham radio sites to figure out how to improve the range of your antenna. Keep in mind that the goal of many ham radio operators is incredible range, but that can come at the cost of broad coverage. Doing exactly what a ham operator does may give you the results they want, not what you want.
YOU want to hit as many high scale hotspots as possible. You’ll usually do that by using a low gain antenna up high, with clear lines of sight all around.
Remember, you’ll earn the most by delivering the most valuable & provable coverage to the network. The concept is simple. The execution can be complicated. If you want help with getting the maximum value out of your placements or strategy, I’m available for hire.
For those of you who skipped all that and just want to know what antenna to get, here are 4 generally good options for the 3 most common scenarios.
- In a building in the city? Get an outdoor HNTenna or a McGill in the 3-6 dBi range, put it outside up as high as you can.
- In a building where you just can’t get up high? Use the stock antenna that came with your hotspot. Also, find a better placement location. You did read about that, right?
- In a suburban house? Get either the HNTenna or a McGill in the 3-6 dBi range and put it on a pole outside and up high.
- On a mountain where you can’t possible transmit behind you (because the mountain will block your signal) and you have an enormous view of civilization and your nearest hotspot is more than 5 miles away? Try a 8-9 dBi patch antenna, like these.
I’ll round this out with what to definitely NOT do. Don’t just look at the gain of an antenna and think higher is better. Don’t bother with Yagi antennas. Finally, don’t worry too much about your antenna. In the big picture of earnings, it is FAR more important to have good placement and elevation. The fanciest, coolest, most high tech antenna in the world won’t get you much if you’re in a crappy location down low.
Best of luck with your placement and earnings, I’m stoked to be a part of this amazing community! If you’re looking for work in the Helium ecosystem, check out Helium Jobs. You can post and find jobs there, help support the ecosystem by making it easier to connect professionally, and let the world know that YOU exist and want to help contribute within the Network. Rock on!
Resources and Further Reading
A deeper dive into understanding how RF works.
Calculating RF Power Values (explains why a 6 dBi antenna doubles your power)
900 MHz: The Wireless Workhorse. (Probably why Helium chose LoRa)
List of Helium Hotspots & Their Antennas
Before you read this and assume that you must have a high gain antenna in order to get great earnings, please keep in mind that these hotspot owners are generally tinkerers and often have some expertise in RF theory. The results are a little skewed because of that.
UPDATE: HeliumVision now reports this for all hotspot owners who have entered this on Helium app. I’ve closed submissions on this page.
Docile Bone Pony – Elevation: 16 stories, Area: Greater Boston, MA. Antenna: 8 dbi omni from eBay, Cables: 60′ of LMR400
Sweet Sage Pike – Elevation: 43′ above ground, Area: San Diego, CA. Antenna: Nearson 9, Cables: 5′ of LMR400
Chilly Blood Mongoose – Elevation: 41′ above ground, Area: San Diego, CA. Antenna: Laird FG9026 (6 dbi), Cables: 5′ of LMR400
Lucky Menthol Wasp – Elevation: 60′ above ground, Area: San Diego, CA. Antenna: RAK 5.8 dbi, Cables: 11′ LMR400
Nice Lipstick Chimpanzee – Elevation: 25′ above ground, Area: San Francisco, CA. Antenna: RFMAX | ROSA-900-SNF, Cables: 5′ LMR240
Interesting Pearl Starling – Elevation: 35′ above ground, Area: North Shore, MA. Antenna: RAK 5.8 dbi, Cables: RAK pigtail interface converter bundled with antenna
Jumpy Iron Ferret – Elevation: 34th story, Area: Chicago, IL. Antenna: Stock, Cables: N/A. Indoor setup.
Kind Infrared Lynx – Elevation: 15′ above ground, Area: Denver, CO. Antenna: Taoglas 8 dbi. Cables: 15′ LMR400
Lucky Dijon Scallop – Elevation: 33′ above ground. Area: Englewood, CO. Antenna: RAK 8 dbi. Cables: RAK pigtail cable
Sticky Pear Dolphin – Elevation: 311′ above ground (mountain). Area: San Francisco, CA. Antenna: Oukeione 3 dbi. Cables: Bingfu
Petite Menthol Leopard – Elevation 25′. Area: Napa, CA. Antenna: 5.8 RAK. Cables: Bingfu
Best Tangerine Racoon – Elevation: Second Floor Window. Area: Bayonne, NJ Antenna: Stock 3 dBi Cables: 1m pigtail
Warm Juniper Panther – Elevation: 4th floor rooftop. Area: Bayonne, NJ Antenna: Nearson 9 dBi. Cables: 4′ LMR400
Scrawny Eggplant Panda – Elevation: 35′ Area: Lakewood, OH Antenna 4 dBi Multipole Cables: N/A
Ancient Cider Grasshopper – Elevation: 40′ Area: Kansas City, MO Antenna: RAK Wireless 8 dBi Cables: 30′ LMR400
Oblong Slate Platypus – Elevation: 400′ Area: New York City, NY Antenna: Proxicast 10 dBi Cables: LMR400
Ripe Banana Goblin – Elevation: 2nd floor window Area: Vancouver, BC Antenna: Stock 3 dBi Cables: N/A
Trendy Rainbow Lizard – Elevation: 1st floor window Area: Vancouver, BC Antenna: Stock 3 dBi Cables: N/A
Striped Pewter Osprey – Elevation: 20′ Area: Los Angeles, CA Antenna: RAk 5.8 Cables: LMR400
Nik,
Thank you so much for your hard work and support to the community,
I’m looking for the SenseCAP M1 hotspot EU868
I’m in France, it work on other frequency and I’m a bit confused about the best setup to choose in my case,
I’m in a small building at the first floor so not so high, other buildings are higher
the building is located around a circle place with other buildings around the circle and some trees
in the middle of the circle place there is two streets crossing each other with car traffic and a subway station underneath
In the back of the building it is enclosed space with other buildings
Also there is already 2 hotspot already visible on the map around about 150 meters (500 feet) away each
– should i use the 2.8 dBi because of the round circle space at short distance ?
– or the 5.8 dBi to go through the few threes and many cars ?
– or the 8 dBi to go through all buildings through the place ?
Thank you in advance for your time,
Hi Yoann, 5.8 will will probably be fine for ya. Rock on!
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Good morning, I have a 9dbi mcgill antenna on the roof at 20 meters height + or – I leave a hospot link but it gives me invalids in several hospots at 30km… https://explorer.helium.com/hotspots/112gw67DtWkv9oK6kGi3EX2LnKZPAU4D5AeYR1EtF8P42sfamUsW help please simulation , Would a 6dbi mcgill one be better?
I’d look at how many invalids vs valids you’re getting, and which are high and low value. Does that make sense?
Nik, you are a great help to the community, much appreciated.
I’ve spent a considerable amount of time trying to find a straight answer to this, but apologize if you’ve addressed it before.
Currently, What happens if you don’t update your aftermarket antenna specs on the Helium app? Will it affect the performance on the antenna if the info is not updated correctly to reflect proper DBis?
Would the update be needed for each antenna/gain option to actually reap the benefits?
As a rule how long would you run each gain option as a test to have an appropriate data sources to pick a winner? Then once you pick a winner update the specs on the Helium app?
Cheers
Richard
It’ll decrease signal strength if you assert a gain that puts you over the legal limit. More over here.
7 day minimum to get good numbers. Check the YouTube interview with Matthew Patrick for more on collecting good stats for Helium related decisions.
Hey Nik,
I live out in the country with hills and trees, my nearest fellow hotspot is over a mile away. s it still worth it to set up a hot spot?
Gunny
Hey Gunny, if you’ve got a clear line of sight to that other hotspot you’re likely to connect with it. LoRa can easily do a mile. Ideally you’d want a few other hotspots AND have a use in mind for the coverage Helium provides.
Hi Nik- I bought the Peoples Antenna based off your recommendation above. They charged my card but never received any order confirmation and they won’t return support emails. Have you found them to be a generally good company? Do you have a backup budget selection?
Thanks for the great content!
Any suggestions to maximize my earnings
Sensecap M1 with 5.4db antenna placed on the second floor in my house next to the window currently getting around 3$ worth of HNT
If I buy a higher DB antenna my earning would increase? whats the best one ? saw filters? Amplifiers? Seeing many things online and getting confused as I dont want to spend too much so what would be my best options
https://explorer.helium.com/hotspots/11ADQM15ioZM4KnQoTG7sUAfFe73mox61fdSpZmzUFQcFXKjxyy
Higher gain antenna probably won’t do as much as getting your antenna outside and up higher. 🙂
Hi Josh, they’re a generally good company, though growing fast and will have stuff like this slip through the cracks. I’d re-ping them on email one more time, and check through your spam for confirmation. McGill are also good antennas.
Hi.
I want to get Senscap M1 with antenna but I don’t know which antenna shoud i get…
This is my location https://explorer.helium.com/hotspots/hex/881ec152b7fffff
Behind me It is suburb area with 1/2 houses everywhere and in front of me it is pretty much wooded area.
What antenna shoud i get 5.8 , 8 , 10 . Which one should be the best in my case?
Hi Georgi, I think you’d be fine with a McGill 6 or maybe higher. Remember, it’s more a factor of how high you get your antenna and how much line of sight it has to other antennas than it is which antenna you buy.
I would probably put it on 10 meters (+- 1-2 meters). I don’t know which one should I choose. I would really appreciate it if you tell me which one in particular is the best. This is a reply to your comment APRIL 27, 2022 AT 7:38 AM.
Thank you in advance,
Georgi
Hi Gerogi, click this link to go to the McGill 6 dBi, which should be fine for you. Remember, the antenna doesn’t matter as much as the elevation.
The elevation in my city is around 390 meters. Will the 6 dbi antenna be the best choise for me?
Hi Georgi, citywide elevation has very little to do with what antenna you should use. It’s the specific elevation at the point of install, and how much clear line of sight (to other Hotspots) that gives you. The 6 dBi should be fine.
Hi nik this my location and i want your advice which antenna you recommended to use
https://explorer.helium.com/hotspots/11e9gtZYsxr1EE42SdipydLU6Ti3PJVXpdNRqAZv3W8XFRwBqgZ
I just want to know where to get the equipment your using
Anything in particular? McGill’s got a wide range.
Hey Nick, quick question. My buddy says to purchase a ‘signal booster’ which attaches to the Miner (Bobcat 300 – in my case) to boost signal ex: FBP-915S. Not near any cell tower and antenna is high above the roof lines in a suburban neighborhood. My first thought is overkill and signal loose out of the gate. Should I consider this booster add-on or chalk it up as BS?
Thanks for your time, Nik!
I wouldn’t worry about it, but only testing will tell. I haven’t used a signal booster on any of my setups so far, and some of them are miles from the nearest Hotspot. All performing fine.
Is there info on here about how to get my Bobcat out of relay mode?
Yep, go here. Light Hotspots should make this a thing of the past.
how many km will the 5 dbi – 9 dbi antenna’s reach in ideal location? what do they max out at?
Oh, 200 km with clear line of sight is not unheard of, and that’s for a 3 dBi antenna.
Hey Nik, great job with the information above. You are a master at this and a fantastic member of the community. I recently got my Bobcat 300 and was wondering if it would be safe to put the stock antenna outdoors on the roof for example for better coverage. I really feel that it would improve my earnings as currently, I have it set up inside next to a window. Also, and sorry if you had already addressed this, but would the connection from a wi-fi signal (the signal is coming from an extremely stable 4G connection from a router) be much worse than ethernet? Thank you in advance and keep up the great content!
Hi Lyubo, fine to set up the stock Bobcat antenna outside, I believe it’s outdoor rated. Almost always better to get the antenna outside & up high if possible. As far as WiFi vs ethernet, I always figure out how to connect to ethernet cables as that avoids any issues with WiFi, but if WiFi is your only option that’s fine.
looking to getting into mining is a 15dbi over kill looked online and seen one that is compatible with a bobcat 300, I live in an area that is mostly flat and lots of trees. I would like to get as much range as I can or is there a limit on what I can use. I live in Michigan
Hi Hangman, yes, 15 dBi is overkill. You’ll probably be best served with a 9 dBi, just get it up as high as you possibly can. Location is far more important than antenna (or elevation, for that matter).
Hi Nik.I hope you can help with this.
I live in Gillingham dorset in UK at altitude 70m.there are a few hotspots in my town but they all seem to be inactive. in town 4 miles away from me there are hotspots which are working fine but the town is at altitude 200-220m, there is a chance to connect with them but what antenna should I buy? 6dbi, 6.5dbi or even bigger ?I would say my town is between the hills.
second issue is placement of hotspot. In attic is usually 33C. is that too hot for miner?i can place it on second floor of my house but will have to run a 5m cable. what would be the best?
hope you can help.
regards
Hi Martin,
No antenna will blast through hills. There’s a chance the signal will bounce off something and get to the far side, but that’s unreliable. In general, 6-9 dBi is going to be your range, and anything in there should work well.
The best place for an antenna is up high, the best place for the miner is usually somewhere in a temp range humans can tolerate. Specific miners have specific temp parameters, double check yours. I’d run the 5m of cable to keep the antenna high and the miner out of the heat.
hi.
Thank you for your response. the stronger antenna, less beamwidth it has, for example 6,5dbi has 30degrees vertical, but 8.5dbi has only 10degree vertical. would that matter around hills?so can 6.5dbi reach higher over the hill then 8.5dbi?Am i understanding right? I am thinking about 6dbi but if 7 or 8dbi will work better then I will go for it.
regards
Don’t worry so much about the “right” antenna. Location is far more important. Antennas don’t really matter. Any decent brand from 6-9 dBi will do as well as anything else in the location you’re describing.
Hello,
We are having Milesight helium hotspot, model:UG65-868M-EA-H32.
Please can you recommend the suitable antenna models for this hotspot to improve coverage and earnings.
https://explorer.helium.com/hotspots/1121aRSBSxheung9eFVStXmcV3hsyjU6wcWYkhUNeVGBD8H1qPKh
Thanks,
hi.
Thank you for help. 6dbi antenna bought and instaled. I had 4dbi antenna for 2 days and then swapped on 6dbi 2 days ago but I can not see any difference in witnesses, rewards etc. is that normal?or should I wait a few more days? regards
Pretty normal. Switching antennas typically doesn’t do a ton to change things; location & elevation are what really matter. I’d wait a few more days to make sure. 7 day minimum for assessing, sometimes more depending on local density.
i live 7 miles and have a 50 feet or so placement what dbi antenna should i get im so confused
Hi Jeremy, don’t worry too much about the dBi. It won’t make a huge difference. If you need “buy this antenna” advice, I’d just pick up a Parley Labs 5.8.