Yet another update, after 3 days of rain, the sun came out and my rak node came back to live. So it seems the brownout issue seems to be fixed by using the board.
I now have two boards connected to two different rak’s but i use the same model of solar panel to test. (5V 1.5W).
I also slightly changed the test setup, the solar panel is now directly connected to the board, without any boost or step down module in between.
What i’m currently trying to test is if it stops charging if battery is full. But currently the sun does not want to play ball.
To get solar panel out one just has to file away a small dent in edge of box where lid already has an indent.The hole for the antenna needs a 6.5 mm drill bit. Drilling it in one go in plastic is a bit much, start with a smaller hole and then use the 6.5 mm drill bit.
Circuit is nice and small. Very compact build indeed. Not totally waterproof but enough to test the solar charging.
Update: this node did re-start after brownout with the circuit in this post. Another update: just as with some other solar battery management boards I use, when I put this node in a location that was very poorly illuminated, it was possible to re-establish bluetooth with the device, but all the settings had gone to factory settings, and so the node is not “spring on” for that reason.
if battery is full. But currently the sun does not want to play ball.
