If you’re setting up a miner for the first time and your location is near the boundary of a Hex, you have the flexibility to pick either the location you’re exactly in or an address close by – in the neighboring hex.
But does it really matter?
The answer – It really does not matter as long as you’re no further than about 100 meters away.
It’s also important to remember that transmit scales (that depend on the number of hot spots in your hex) affect hot spots that witness your beacons, so it will affect others more than you. At the same time however, you will get less rewards from sending beacons. But this is not going to impact your earnings by very much.
The reason for this is that most rewards come from witnessing other hot spots. Hotspots only beacon 2 or 3 times a day on average – sometimes even less. However a miner with a good antenna will witness beacons many, many more times a day.
What is a Hex?
From the Helium Documentation
Hexagons, while also a six-sided shape, is the underlying representation of the earth on the Helium network. Based on Uber’s H3 index, the surface of the earth can be represented by a grid of hexagons at different resolutions, with higher resolutions covering a larger area, and the smallest resolution covering centimeters of the earth.
This is very similar to how the earth is represented for cellular network planning. The hex represents an area where a group of distinct frequencies are uniquely assigned. These frequencies can be reused in another area as long as the two areas do not intersect. If they do, then there’s the risk of RF interference.
The picture above shows the Hex grid with cellular infrastructure.
In the case of Helium the use of this basic shape is to maximize the geographic distribution of hotspots. There’s no point in having all the miners in downtown Chicago, for instance. This is why there’s incentives to place miners in areas with low density.
Helium and Hexagons
In the early days of Helium, there were no more than one miner per hexagon. These days in urban areas, there are tens if not more Helium miners per hex. The larger the number of miners the lower the rewards.
For this reason there are a number of spoofing attempts where people will place miners in Hex areas where there are no miners. This attempt to game the system works for a while until the miner is caught and added to the deny list.
How far can my miner communicate?
Helium miners use the LoRa protocol for wireless communication with other miners. This utilizes frequencies 868 MHz and 915 MHz in most areas of the world.
To understand how many Hex’s can be covered with your miner, use the free space path loss calculator for an ideal estimate. The actual number might be much lower depending on various factors. For instance this post explains the range using an 8 dBi antenna.