After a summer with failed attempts to get the water temperature and tide from the local pier all the way to my site I had to search for alternatives. The cause of failure was strangely enough not my coding or soldering. It was the basic issue with WiFi range and power usage. Hence I had to start searching for alternatives for some Long Range wireless transfers. I had briefly heard about LoRa, since a friend had been a TTN backer, and now it was time to read up.
As a happy coincidence PiSupply suddenly asked on Twitter (for once real use of that platform) for beta testers to their new IoT LoRa Gateway HAT (which has now been funded in their Kickstarter campaign). Luckily I ended up as one of their 50 beta testers and have now got the HAT in my hands.
The HAT is built on a RAK Wireless RAK833 module which in turn has an SX1301 inside (according to the label).
Other beta testers have already shared their experiences with the HAT. Alasdair Allan has a review on Hackster.io with deplyment onto TTN and Nicloe has some nice pictures and comments about the few hurdles in the assembly.
The package contained the HAT board, RAK833 module, header, antenna, pigtail (RP-SMA), heat sink, and four spacers (the SD card adapter is only for scale).
The assembly was really simple – no soldering! Not even the header. Only things to be aware of (at least places where I stopped and made a second judgement) were first that it takes some force to push the header in. Second, that the black plastic clip (where the RAK module is locked down) should be removed. And finally don’t forget the heat sink. The RAK module does get warm – see below.
Pi Supply has made three options available to get the needed software. One can choose to build and install from the source at Pi supply Github, deploy using Balena or download the prebuilt SD Card image. I chose the latter – the super easy SDCard Image setup. For anyone who has ever downloaded Rasbian onto a Rapberry Pi, this is just as easy. The setup page also guides you through the setup in The Things Network (as does the Hackster.io article).
So easy that is was almost a bit boring – up and running with blue light on the board and green dot in the TTN console without any coding. I should maybe try a different installation approach at some point to learn what’s behind the scene.
When finished with the gateway setup, it’s time to make some applications/nodes. The gateway does not really do that much by it-self. More nodes are in the mail as I write this, but right now I have only one node which I tend to use for tracking of the gateway. I have planned for two so fare; a stroke counter and a replacement node for my temperature/tide project.
As the RAK module gets rather warm I was a bit curious and was able to borrow a thermal camera. Also it would be nice to know where the best place for the heat sink was. From the first picture (on the left) it looked as though the best place would be on the sticker. But by touching the module (carefully) it felt just as warm on the shiny part. Therefore, I put a piece of normal office paper on the module and suddenly the camera saw the same temperature as on the sticker. For some reason the camera was not able to read the temperature on the shiny part of the module.
After adding the heat sink the temperature dropped a bit. It is still a warm module, but I’ve not experienced any problems related to the temperature.
I have got myself an external RAK Glass Fiber antenna. As of now it is not up on the wall yet, but I have made a bracket for it found on
Thingiverse. Hopefully I get the time to climb up on the roof and mount it before the snow comes.