Solar charger for gotenna


#1

This solar panel from Amazon (ALLPOWERS 2.5W 5V/500mAh Mini Encapsulated Solar Cell Epoxy Solar Panel DIY Battery Charger Kit for Battery Power 130x150mm (Solar Panel Only)

Will charge a GoTenna mesh node during the day, enough for 24 hours. The GoTenna draws about 270mA when charging, and this solar panel can easily source this.

I put a 5.1V 5W zener diode across the panel
In case the mesh didn’t like the full 6V open circuit voltage of the panel.


#2


#3

@Rob_NZ6J I am not very electronically savvy. Does the goTenna Mesh internal hardware act as the solar charge controller to prevent overcharge (sort of like what I assume happens when you charge it from other USB sources and it “stops” when fully charged)? Are you setting this up for the purpose of setting the Mesh device as an unattended relay node?


#4

The zener diode across the
Solar panel provides over voltage protection. As you suggest, the internal circuitry of the mesh handles the charging as it would with any other power source.

Yes, this is for remote mounting of a node.

Best regards,
Rob Rowlands
415 894 9036


#5

Thanks Rob! Great info!


#6

Does anyone have a solar charger battery pack that can attach to a car window? I’d like to put relays in each of our cars but the lighter plugs only operate when the vehicle is running so I need a solar+battery pack that I can just leave attached to the car window to keep gotenna charged and running.


#7

See linxada on Amazon, it’s advertised as 10 Watts but only delivers 4 Watts. This is enough to charge the mesh units however.

Best regards,
Rob Rowlands

415 894 9036


#8

My cars are like this, too. I’ve found that a Voltaic V15 in Always-on mode between the Mesh and the car is enough to keep the Mesh going in unpaired-mode with about an hour of driving each weekday (Monday-Friday). You might need more if you drive less or want a phone paired full-time.


#9

Another option here is to get a USB buck or boost/buck converter circuit board. These can be gotten for maybe a dollar or two on sites like Aliexpress or Alibaba (or elsewhere). Efficiency is generally better than a zener diode, especially if the voltage of the panel is MUCH higher than 5V.


#10

I would like to setup a GOTENNA MESH node, I agree that the node has an overcharge protection.
Thank you for the info.
Carlos KA9JYO