The SenseCAP M1 miner is one of our top picks for Helium hotspot. It beats the Bobcat 300 on several different specifications.
In this post we will discuss antennas that can improve the earnings of the SenseCAP miner. Let’s get into the details
Table of Contents
SensCAP stock antenna
This miner ships with an omnidirectional monopole antenna similar to other miners. The gain of this antenna varies depending on your region.
| Region | Antenna Gain |
| US915 | 2.6 dBi |
| EU868 | 2.8 dBi |
| AS923 | 2.6 dBi |
In the case of these antennas, beacons are transmitted equally in all directions. As well the antenna will witness beacons from all directions uniformly.
Increasing HNT Rewards
One of the easiest ways to increase your earnings is to witness beacons from miners that are in a hex region with high transmit scale. In the picture below, areas of the map with low transmit scale are indicated in red, while regions where miners have high transmit scale (close to or equal to 1) are indicated with the color green.
One way to witness beacons from hotspots with high transmit scale is to be physically closer to them. Not too close though as if you’re closer than 300 meters there is a good chance that the reward will be invalidated.
The other option is to use a high gain antenna and place your antenna either in your attic or on the roof of your home.
Antenna Gain
There are many alternatives to the stock antenna. Let’s take a look at a few of them. The first one is an 8 dBi antenna from Embedded works.
Based on observations we have made, with proper placement and under the right conditions, a range of 60 km (37 miles) can be achieved with an 8 dBi antenna. That’s adequate to reach the green areas if you have a miner in the red zone.
Another lower antenna gain option is the Eifagur 5.8 dBi.
This is a lower gain antenna that is shorter in length (16.5 inches relative to 45 inches for the Embedded works antenna). The white shell of the antenna is made of fiberglass to make it waterproof. The antenna structure inside is made of copper.
RF Cables
The Eifagur 5.8 dBi comes with KSR200 cable and it loosely matches the performance of LMR200, but at a lower cost.
The 8 dBi antenna includes CLF200 RF cable of different lengths.
The following table shows how these cables compares with LMR400 which is a popular high quality cable.
| Antenna | Cable type | Attenuation per 100 ft |
| Embedded Works 8 dBi | CLF200 | 10 dB |
| Eifagur 5.8 dBi | LMR200 | 10 dB |
| LMR400 | 3.9 dB |
The loss from a 100 ft length of LMR400 cable is more than 6 dB lower than that of CLF200 and LMR200. This will result in signals that are about 4 times weaker in the case of the lower quality cables. Weaker signals result in fewer witnesses and lower HNT earnings.
Within the context of the picture above, use of the CLF200 and LMR200 cables between the antenna and the miner will prevent a miner in the red zone from witnessing beacons from miners in the green zones.
For long cable runs we recommend using higher quality LMR400 cables as the loss or attenuation is much lower. This will result in more witnesses and therefore more HNT earnings.
High Gain Antenna Trade-offs
The higher the gain of the antenna, the more focused the beam. The picture below from RAKwireless shows how the beam narrows as the antenna gain is increased.
It makes sense to experiment with all three different antennas to see what earns you the most HNT.
Summary
In this post we have provided a couple of high gain antenna options for the SenseCAP Helium miner.
These will extend the range of both beacon witnessing and transmissions which in turn will increase HNT earnings.