Ian Dunn on Nostr: Here's my first #meshtastic rooftop node. I find it really odd how seemingly every ...

Here's my first #meshtastic rooftop node. I find it really odd how seemingly every #rooftop_node out there is in direct sunlight on a blazing hot rooftop like mine and yet they all still use lithium ion batteries. I get that lipo batteries are in fashion but they really aren't great for a harsh environment.

So I've gone on a mission to develop this little lead acid solar charger PCB. Just plug the heltek in and it supplies power. It's got 2 buck converters, the first stage is there to make sure the battery gets a nice even voltage from the solar. The second is to step 12 volts down to 3.3 volts for the Heltek. It has a low voltage drop out chip to keep the battery from being discharged too low. It has 3 status LEDs to indicate the status of the 3.3v rail, the 12v rail and the solar input. The LEDs can be turned off with a single switch to save power. So far it's working great! I've had it running since spring and it hasn't crashed yet.

One of these days I'm going to put it in my freezer to see how long until it crashes, and how long it takes to come back. I'll open source the design when I finish a few more enhancements.

#electronics