Introduction
This is a second experiment, following Meshtastic to connect isolated villages, using LoRa as emergency communication for remote villages.
The Tukano people are indigenous to the deep amazon jungle, more specifically the Upper Rio Negro region. Together with local collaborators and the Nova Era Institute we’ll be working with them in a 3 year long project to strengthen their autonomy through communication and information technologies and agroforesting projects.
In the first steps of the Tukano Project, the critical needs for 3 communities within the Balaio Indigenous Territory were assessed. The need for ways to communicate between the villages and ideally to the closest town (75Km far) are in times a matter of life or death. They also really need some access to useful information, such as learning materials for the topics that are relevant to them and healthy enterteinment, that are also relevant to their culture. And longer term, they seek food sovereignty.
The first action for the project will be to setup the communication and information infraestructures. We’ll be arriving in the town of São Gabriel da Cachoeira, and will setup a base there, with at least one RPi 4 and one LoRa radio, connected to each other. We’ll have RPis and radios powered by a 150W + 70ah solar setup in the 3 villages as well. Ideally we’d be able to connect this town node to nodes in the villages, creating an emergency communication channel and remote tech assistance using the SSH over LoRa tecnique.
The geography seems helpful, but it’s amazon jungle vegetation, which I’ve never worked with. I’m hoping we can work thru the gigantec trees, but not sure how. Also we’re still seeking permission to put radio nodes on top of the estrategic hills.
The easiest way would be thru a direct 64.3Km link, probably using the same setup as on the previous experiment. A disadvantage is that the road in between the hills would probably not get coverage.
This is a second way of doing it, with a node on a hill 19.3Km after the town and 45Km before the village hill. These links could be done with a moxon or a more powerful omni. The advantage is that there will coverage along the road, which can be very helpful. But the disadvantage is that we’ll be to deal with one additional hill with gigantec trees.
Questions
Frequency
If we choose to ignore the legality of it, would using the 433Mhz radio be helpful in going thru the dense forest? If we find out we can’t go above the canopy, could making smaller ~2Km 433Mhz links through the trees work?
Antennas
I’ve only experiment with direction and stock omni antennas. Ideally we’d be using more omnis in order to get better coverage and a more mesh-like network topology. I’ve seen the discussion on fiberglass omnis, and it seems they might be a good choice.
I’ll currently looking at these RakWireless 8dBi fiberglass omnis for 915Mhz, but there are cheaper options such as the Zizor 8dBi fiberglass omni for 915Mhz or a generic 8dBi fiberglass omni for 915mhz, also with a 433mhz version if we go decide going for that. Should we expect much better signal quality and durability with the more expensive ones? How far should an omni such as these could go in a line of sight or through the jungle trees?
In this coverage simulation 433Mhz seems to perform much better. Could I realistically expect such coverages with those 8 dBi omni antennas?
Devices
I’m inclined to use T-Beams again, but using the new nrf52 boards would be amazing, to take advantange of the near 0 power consumption when idle, the sd card slot and the e-ink display. Just not sure if they’ll start shipping on time or if they’ll be much more expensive. Any updates on them @geeksville?
Else using other nrf52 board, such as the already supported Rak815, for the repeater nodes and T-Beams for end-user nodes.
Energy and casing
I’ll continue using the same solar setup and casing as the previous experiment, even though I didn’t get a chance to really know if they were a good choice, as our Krahô partners took them down when heavy storms started.
That raises a question about lightning protection. Should we be installing lightning rods close to our nodes in order to protect them from strikes? That would considerably raise the price for each node.
Something I’ll add which I think will give more waterproofing to the case are cable glands.
Maintanance
The ability to get/update settings of a remote device using LoRa would be a huge advantage, and I remember @geeksville mentioned this was on the way. Has is happened? Are there docs or any discussions I can follow to understand how this will happen?
Innovations since last experiment
Meshtastic devs are in a row, can’t congratulate yall enough 
I’m excited to test the new features that are coming out such as the Range Test plugin, the Store-forward plugin and specially everything related to web integration: Meshtastic over WiFi, Meshtastic web-ui and meshtastic.js (which a have billion ideas for).
Other then these new features all the bug squashing is really exciting, as I experienced some difficulties with the firmware I had at the time (October 2020).
Ordered some more T-Beams just to get back to doing more tests and working on the video-documentations. Let’s get to work 
