Exactly
5w solar panel is not enough for one or two 18650 batteries. You need a 35w ~ 50w solar panel with a charge controller to keep the battery under control.
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Thanks for the tips @Bunplugged and @TitanTronics.
I actually ordered two 5W 5V panels and two regular 10W panels, which I’ll test adding a step-down.
I’m eager to see how well they’ll work. I don’t expect the nodes to run 24/7, will probably need to tune the sleep-time so that they’ll at least have some battery life at night to wake up every hour or so for emergencies.
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One thing that will be needed is the ability to send the status of the battery and solar from logs so you can set the power accordingly. Start small and work your way up. I would recommend 2-4 18650 batteries and a 10w solar panel (regular which goes up to 22v) at least. But I do not know what your usage will be like and you can always add in later what you need. Also assume that at the begining people will not be using it and latter on it will be used heavily. There was a project on hackaday to do a similar thing called Jebel.
Jebel had been shared here before and I’m in love with it, very inspiring. Really where I want to get, and move on to try something like QMESH.
Sending battery and solar status is important. For now I’ll be tuning the sleep time, and once I understand the energy consumption better will adapt batteries and panels accordinly.
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I live in Gurupi some what near this places, if you like I could test a panels some solar panels for you. I have 4 differents panels that i could make a tests for you, i just need your requirements. Do you speak portuguese?
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Quem massa @Hugobrr!
I bought two 5W 5V panels (controller included) and two 10W panels, but still not sure what kinda charge controller can handle it. I’m guessing it’s too much for a TP4056, maybe something like this 5-18V 2A controller?
btw: I haven’t followed this long and excellent sounding thread. But just FYI - I discovered that the current code base was transmitting at a lower power than I thought, so soon (I’ll release the build next week) you should be able to get a few dBm more power.
You’ll definitely want the ‘router mode’ feature before permanently installing the router nodes. That will definitely be done in the next few weeks.
Also - I haven’t carefully checked what radios you are proposing but the new sx1262 based TBEAM I bet has quite a bit more range than the more common old design (just based on the data sheets). However, I don’t think anyone has rigorously tested this theory(?).
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Thanks for the really awesome update @geeksville. I installed v1.0 on all my boards, and it’s working beaultifully, many many congratulations on this and future releases 
Looking forward to test router mode and having more power 
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First prototypes
Reposted from Secure Scuttlebutt
Extra LoRa boards, batteries and cases arrived
Boards 
The boards were a good surprise, in that they were all T-Beams, which are the favorite boards for Meshtastic firmware to run on. Installed and tested all of them, and they are working fine. Also my good friend Tiago helped me solder the little OLED screens onto the first two boards, and the ui/ux is actually quite amazing for such a small display and set of buttons.
Batteries 
I didn’t know there were different sized 18650 batteries, and the ones I bought are about 2mm larger then the usual one, and don’t fit on the T-Beams. Gonna return these.
Went on to buy these hopefully original Sanyo 2600mah batteries. Real challenge finding original, good quality batteries in Brasil.
Cases
When I first saw the cases I thought they would be too small. But it turns out that they fit perfectly by putting the boards diagonally. We drilled two holes on it, one at the top for the antenna, sealed with rubber for now (probably with silicon in the future); and one at the bottom, sealed with epoxy for the usb cable, which will connect to the solar panel, or for the first experiment to the usb of a LibreRouter.
Mesh experiment
While the panels and the yagi antennas don’t arrive, I’ll place one node where our LibreRouter is at the top of the hill, where on the previous test we managed to get a connection anywhere in the village.
I’ll keep one node, and give other nodes to neighbors around the village, and test out our own offgrid chat.
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I’ve looking for parts to buy and replicate the ground plane antenna from the video @PA7John shared.
Found this chassi mount which looks like the one in the video. But I’m having trouble finding the piece that connects to it. It’s a N Male to SMA female, correct? Foud this but the seller says it won’t connect to the chassi. Could someone help me out finding this part?
On the local hardware store I found a cheap copper rod, which looks good enough for making the antennas.
That chassis mount connector is a UHF type not N-Type. I’d try stick to N-Type if you can.
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You’re right @dafeman, thanks. I didn’t realize N-type was different from UHF. Found these N type chassi conectors. So these N male to SAM female should work with it correct?
Mind pointing me to what cable endings I should have? I’m looking something like this 1m cable, does it look right?
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btw - you’ll want to keep cable lengths really short if you can. I’ve heard we lose lots of signal in just a little bit of cable (some RF aware person can probably speak better on this though).
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That 1m cable has F type satellite tv connectors. Ideally you want to avoid extra adapters. Try find a cable the is as short as you need that has an N Type male to SMA male. That will go direct from the chassis connector to the TBeam. Some thing like this
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Thanks for the tip @geeksville, I use 1m pigtails for my mesh routers, so I thought that would be ok. I’ll go for 10cm (4inch).
@dafeman, of course! That’ll make things a lot easier. Thank you my friend. Gonna make some orders today, and start experimenting with ground plane antennas
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A friend suggested I use these bnc conectors instead of the chassi ones, as they’re 10x cheaper. We then have to use some kind of plate to connect the ground plane legs, something like these fenolite plates.
It would make them a lot cheaper, but are there any disadvantages to this approach, besides the extra work?
Those BNC connectors are for CCTV carrying a composite video signal not RF. BNC is common for RF but it terminates to the coax different/better. These also aren’t water-resistant whereas the N-type usually has a rubber seal.
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18650 is the size of the battery and that is what the numbers mean (18 circumference 65 height).What you are probably experiencing is that the battery protection adds on to the battery making it a little bit longer, and this you will lot need if you have good enough firmware. And for those that do want it you can buy plastic holders for 18650 and replace those on the t-beam with a little solder.
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Nice project. Thank you for all contributions.
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@luandro
Pt_br : Eu acredito que a sua bateria seja 2 mm maior pois nela tem um chip controlador de tensão na base abra o plastico e tire ele.
en: I believe your battery is 2 mm bigger because it has a voltage controller chip on the base, open the plastic and take it out.
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