$25 low power dev board with solar: Rak4630 (now included in regular builds)

I placed the Wisblock on a hill for a day and night to test as a go-between part of my mesh. When I left it, the connected 3000 mAH battery was fully charged and the solar panel was connected. For some reason, it shut itself down. I’m not certain if the battery was completely drained in just the over night’s time or if the board shut off by itself, but when I went to collect the board, it was on an “off” condition, ie not showing up on the phone app, all LEDs off. I was able to rouse it by hitting the reset button once. I don’t have the equipment to thoroughly test the battery.

Also, in attempting to upgrade the firmware to the 1.2.38 alpha, the file won’t copy to the board. When dragging the file onto the folder, I think the board boots Meshtastic before the new .uf2 is copied making it impossible to upgrade firmware.

After you plugin the USB, double click the reset button to flash the new firmware.

is the battery charge reporting correctly for you? I get an NA when running meshtastic --nodes for the RAK boards - I dont have a screen for them so can’t say if the info isn’t being sent or isn’t measured.

I get the same (as of 1.2.30) but I haven’t tested the latest. Since this is brand new hardware for the builds, I assume it’ll catch up on a few things like that soon.


Yes, I have done this. The boot loader shows up in my drive list. I open that drive folder, drag the file over it, drop it, it shows a copy progress dialogue, and then about 35-45% of the process, it errors out and says it is trying to copy to a ‘device that does not exist’ as Meshtastic boots on the board.

I cannot do the process quickly enough to stop the error from occurring.

I recall having a copy interruption as well for (1.2.28 → 1.2.30), but in my case, it was a false negative and the firmware did end up showing as updated in the meshtastic app / python api after the process.
You may double check to see if yours updated and didn’t just appear to fail. I think what happens is that once the boot loader gets that new .uf2 file, it immediately boots into the new firmware image before the file handle is closed so windows flips out. I could be wrong though.

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Ah…I had not considered this possibility. I’ll check it after work and report back here.


It’d be great if you could check the battery’s state of charge, as if it’s fine then you’re probably running into this bug instead.

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Checked the firmware of the Wisblock board in the phone app and as you said, it did indeed update the firmware before Windows threw the error! It is now running 1.2.38.

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Awesome! Glad to hear it worked. I was a bit concerned at first when it threw the error at me as well.


Not sure if this is a good place for a discussion on this board’s behavior, feel free to move it if not.

After having figured out the firmware situation, I placed the Wisblock in my parked vehicle all day with power via USB car charger. When I left the vehicle, it was on and showing on the mesh. After around 7 hours, it dropped off of the mesh. When I returned to the vehicle around 9 hours later, the Wisblock was off despite being powered.

Feature? Bug? LOL

If it was a usb car charger and your car was off, it wasn’t probably not providing power? That’s been my experience at least, with car usb taps and cigarette lighter usb power.

My Wrangler has one switched 12v “lighter plug” and one “always on” plug. The Wisblock was plugged into the always on side. I am 100% certain it had power all day.

It seems to stay on for around 6-7 hours then shuts itself down regardless of power state.

An update:

I’d originally placed the Wisblock on a mountainside to operate as a router(is_router true) in a sizable mesh I’m building in rural, mountainous terrain. The farthest node-to-node reach is 11 miles and with the leaves coming in on the trees, that connection was getting spotty. The Wisblock was going to cut that distance in half or so.

It dropped off the mesh overnight and I retrieved it assuming the battery was dead(changed from is_router to is_low_power). I placed it in my vehicle at work powered by USB. It dropped off the mesh.

I brought it home and set ‘is_low_power’ to false yesterday evening. It has been on and running on battery since. BT is sleeping and I didn’t attach a screen as my original intent for this board was to be a router.

It seems that power management is bugged maybe?

Not sure, but my remote solar node deployments with the RAK boards have not had the router or low power settings on. I figured it wasn’t necessary to change the power behavior since the usage is reportedly so low.

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Do you have the GPS module installed in your nodes? Curious as to how your solar panel cases perform since @geeksville mentioned the GPS rail being powered all the time. Had any issues with keeping power going?

I placed the Wisblock setup in a pretty difficult to get to spot on top a ridge and am hoping the panel can keep the 3000mAH battery alive until at least the next firmware update for Wisblocks. Haha

Mine is just the standard evaluation board with no screen or gps. I suspect that even with those rails being powered all of the time, if there’s no gps peripheral on it, it isn’t affecting the current draw in a significant way.

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No screen, but I do have the GPS module installed.

Latest update in my Wisblock saga:
After staying on all night without issue, I put a full charge on the Wisblock and climbed a powerline cut through some gnarly underbrush to a ridgeline and placed the Wisblock there in a tree. Before I hiked out, it was on the mesh and connected to both nodes that it was to be the go-between for. A short time later, it cannot be reached at all even with direct line-of-site and only a few hundred yards away.

Guess I’m crawling through that thicket again in the AM. =(

I think I figured something out… and it explains why my solar deployment works and why yours drains quickly:

The solar power JST input just doesn’t work in the 1.2.30 firmware at all from what I can tell. I haven’t flashed it to the latest but I don’t think anything has changed in terms of power logic for the RAK boards. I supplied 5v to it (and yes I checked the polarity), and we get nothing

Switched to a micro USB breakout (like I used in my last solar setup with power manager board + 18650) and we get power:

Try yanking your battery JST while power is supplied via the solar JST. I bet your board will power off. I’m not sure if it’s solveable by some pin mapping in meshtastic device or if this is something just hardware implemented on the RAK 5005 base board that needs intervention somehow. I may do some reading in the datasheets tomorrow.


Makes total sense.

That could explain why, when placed in direct sunlight without a battery attached, the board seemed to be unable to boot and run on the panel alone. When I first received it, I noted that behavior in my short review but mistakenly thought the small solar panel was simply underpowered. I also noticed that when the battery was attached and charged and the panel went from shade to direct sunlight, it would reboot.

When I mentioned it ran all night without a problem, it was obviously inside out of direct sunlight and when I placed it on the ridge with a fully charged battery, it was early in the morning and overcast. Later in the day, the clouds cleared away and it was sunny.

@Muscles I was experiencing something similar to you when I was on USB. Issues with flashing and booting issues. I updated the bootloader to the latest version and that seemed to fix things: Quick Start Guide | RAKwireless Documentation Center


I’m testing one of the two RAK boards I’ve received today.
After successfully uploading the 1.2.39 firmware, I’ve noticed it wasn’t working anymore after a reboot, so I’ve updated the bootloader (thanks @KevinKW87 for the link!), re-uploaded the firmware and that apparently fixed the issue.

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