OK, after countless hours and months of waiting for parts to arrive, I finally have a decent prototype!
https://image.nostr.build/ce57c6bfff05c7d188d65f09b1c48158b4076086d3a8052adaf716e9fa1675aa.jpg
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Looks good! I tried and failed recently to get an ESP8266 + 18650 to run 24/7 off a small solar panel.
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