Amplifiers can make a massive difference in the reach of your cluster. A well placed antenna will have a very good reach for devices within line of site, and the 915/868 mHz frequency does penetrate obstacles somewhat. However, an amplifier can have a significant effect on the reach and reliability of your cluster. Your laws may vary, so this information only applies within the US.
My understanding is that without any licensing requirements, a person in the US is allowed to use devices that transmit at a power of up to 1 watt legally. Well, it just so happens there is a nice Sunhaus 1 watt amp available on Amazon (when you can catch it in stock). There may be other compatible amps on Amazon and other sources as well, but any amp you try to utilize needs to be specific to the 915 mHz range (or 868 if that’s your thing). It also needs to be bi-directional, meaning it’s just just boosting your transmission power, but also allowing you to receive on the same connection.
View the latest ChatterBox antenna distance ratings to see how these two amps can affect clear line-of-sight distances. The testing is still ongoing, but results will be updated in that PDF as tests are complete.
Sunhaus 1 Watt  | This Sunhaus amp runs on 5 volts and I ran it non-stop it non-stop for months at a time as part of my “base station” node with very good results and no issues. It’s a great option for a node you have connected to a well-placed antenna (and power). |
LoRa Off-Grid Power Node | If you have an amateur radio license, you can experiment with much higher power. I am currently experimenting with this 4 watt “Power Node” by loraoffgrid.link, which others have tested to have an almost unbelievable range of > 50 miles. As I have results to share, I will do so here. |
SZUASHI 4 Watt | This is what I’m currently running as the “base station” node at my house. I run it 24/7 and will be able to report on its performance after some more time. So far, it looks like it’s performing quite well, and this thing is extremely reasonably priced. Keep in mind, this is above the unlicensed legal power limit in the US, so you need an amateur radio license to run this legally. Currently you can purchase these on ebay for a mere $35, which seems like quite a deal. |
SZUASHI 20 Watt | I cannot vouch for these yet. Testing is currently in progress. These are available on ebay for around $200. These require an amateur radio license to operate in the US. |
Altware Development LLC is an Amazon affiliate, so purchasing an amp by clicking one of the links above helps to support further development of ChatterBox.