Inexpensive Homemade Outdoor Solar Node

You can build your own Solar powered Meshtastic Node for less than $23. This project was inspired by the exceptional post on the official Meshtastic Blog: RAK WisBlock Harbor Breeze Solar Light Enclosure Hack.

Bill of Materials

• Seeed XIAO nRF52840 & Wio-SX1262 Kit for Meshtastic at $13.49 each. I was able to find these on sale for $10 each with free shipping a few months ago on sale
• Walmart offers the Deck Impressions Solar Wall Wash Light Attaches to Exterior Walls, Fences, Gutters, and Fascia Boards (4 Pack) available for $49.97 with free shipping yielding a price of $12.50 each. Sam’s Club has a 6 pack for just a bit more Deck Impressions Solar Gutter Light – 6 Pack at $54.98 ($9.16 each) with membership
• Wire may be harvested from other projects or procured inexpensively. I used wires with a JST PHR-2 connector so I can quickly separate the Meshtastic node from battery power or swap to another node, even another brand like the Rak WisBlock, for the one enclosure. Be sure to put the male end on the battery and female end on the node and check polarity. Amazon has 10pcs Upgraded Tiny Whoop JST-PH 2.0 Male and Female Connector Cable for Battery JJRC H36 H67 Blade Inductrix E010 E013 for $6.99 with a piece price of $0.70
• Optional: Amazon offers
  915MHz LoRa Antenna with SMA Male Connector for Meshtastic … 915MHz … + 15cm IPEX Extension Cable（2 Sets) for $8.99 yielding a price of $4.50 each

Build instructions:

1. Flash the Node with the latest version of the Meshtastic Firmware at Meshtastic Web Flasher
2. Confirm that each component is working as expected before further assembly
3. Disassemble the Solar Light by removing 4 screws
4. Temporarily remove the 18650 Battery
5. Separate the two boards of the Seed Xaio Kit
6. Solder the wires to the corresponding battery contacts on the Seeed Xaio
7. Optional: Swap out the LoRa antenna IPEX pigtail connector for the Optional SMA pigtail connector if using an external antenna
8. Reassemble the Seed Xaio Kit
9. Solder the other ends of the wires to the battery contacts being sure to respect the positive (+) and negative (-) terminal polarity.
10. Optional: drill a hole in the Solar Light enclosure to allow for the installation of an SMA antenna connector pigtail and also install the LoRa antenna
11. Secure the Seeed Xaio Kit and wires inside of the Solar enclosure. Be sure to route wires so they do not get pinched or damaged during re-assembly
12. Reinstall the 18650 Battery being sure to respect the + and – terminal polarity.
13. Test that the Solar light functionality works. The switch can be used to test the led lights. Make sure to cover the solar panel to simulate dark conditions
14. Test that the Seeed Xaio Kit is functional in your chosen Meshtastic app over Bluetooth
15. Optional: Add a dab of Waterproof Silicone Caulk to seal the hole made for the antenna connector and anywhere else water could intrude
16. Reassemble the solar enclosure using the 4 screws and the two gutter/fence brackets and thumb screws
17. Deploy somewhere with a good view of the sky and as high as possible for optimal LoRa range and Solar power, and enjoy!

You can toggle the Solar Light function on or off depending on your requirements.

UPDATE: Because of concerns about potentially no solar charging occurring with the light switch in the off position, I leave my node enclosure in the on position and snip the wire leading to the LED board to prevent lighting while still allowing for optimal Meshtastic battery performance. The battery will provide about a week of power for the node even without very sunny days. A few hours of full sun per week will keep the node running indefinitely. I have confirmed that I get daytime solar charging with limited overnight power draw since no lights are running.