RAK 4631 solar node (my setup on West Coast Scotland)

Hope to get some repeaters in the hills around here to track us (running and occasional dog deer chase). I’d faffed around with the Lora TTGO but it was apparent it needed a larger solar panel after some testing with a small 6v, TP4056 (with power share mod) and 2x18650. The repeaters need to be discrete. Bit the bullet and ordered a couple of RAK4631’s from Aliexpress and some other bits.
Built the enclosure with a 5v 160mA solar panel (I believe RAK’s box has a 90mA?) and an 18650 wrapped in pipe insulation, we’re pretty sheltered here on the West Coast by the gulf stream and will orient them vertically to shed any bad weather. Aready noticed the battery % hardly moving out of the sun. Its on router but haven’t seen the bluetooth stop yet (does it stay on with the nrf?).
Antenna’s are apparently tuned Puretek off eBay while I await a nanoVNA to tune the whole lot and I think I may need to protect the cell from over discharge (TP4054 on the board)?
Next on the list is a printer for some TTGO/T-beam cases


Repeaters have ben going well for a couple of weeks. Lowest batt was 69%/3.92v and highest after a few days of sun 84%/4.06v. I feel they need a little larger solar panel so have sourced a 250mA 5v which will ‘just’ about fit the box (currently 150mA). I may try 2x18650 in there (again…insulated).


Nice setup. I too have a RAK4631 setup as a router. I made sure bluetooth was switched off via serial USB cable, using https://client.meshtastic.org/

The Boosted RX Gain option may also give you increased range for the RAK4631 (SX126x chip), at the expensive of more battery usage.

Thanks, yes I may turn off the bluetooth, however I was going to do that via bluetooth? I wasn’t aware I could use the rx boost! but hopefully won’t need that. Antennas are supposedly tuned but I’ll check that when I get the vna


What a great place to live in!

More hints:
-If you have enough S/N then you may afford to switch to a faster mode, e.g. from long_fast to medium_slow or so. This leads to shorter transmission times and thus less transmit energy.
-You may also consider to use a better antenna, with some more gain. That gives you more S/N and so you can use a faster mode. This affects the other nodes and paths in the mesh as well…

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Hi Guys - Just to let you know we have a conv for ‘Meshtastic - Scotland’ now.