Solar Panel Keeps Cheap Digital Calipers Powered Up

April 20, 2024 by Dan Maloney 39 Comments

There’s no doubt that cheap digital calipers are useful, especially when designing 3D-printed parts. Unfortunately, cheap digital calipers are also cheap, and tend to burn through batteries quickly. Sure, you can remove the battery when you’re done using them, but that’s for suckers — winners turn to solar power to keep their calipers always at the ready.

[Johan]’s solar upgrade begins with, unsurprisingly, a solar cell, one that just fits on the back of his digital calipers. Like most of these cheap calipers, this one is powered by a single 1.5 V LR44 button cell, while the polycrystalline solar cell is rated for 5 V, so [Johan] used a red LED as a crude voltage regulator. He also added a stack of fourteen 100 μF SMD capacitors soldered together in parallel. The 1206 devices form a 1,400 μF block that’s smaller than the original button cell so that everything fits in the vacated battery compartment. It’s pretty slick.

Given their agreeable price point, digital calipers are a tempting target for hacking. We’ve seen a ton of them, from accessibility add-ons to WiFi connectivity and even repurposing them for use as DROs. Ever wonder how these things work? We’ve looked at that, too.

Hackaday Links: April 14, 2024

April 14, 2024 by Dan Maloney 10 Comments

The Great American Eclipse v2.0 has come and gone, sadly without our traveling to the path of totality as planned; family stuff. We did get a report from friends in Texas that it was just as spectacular there as expected, with the bonus of seeing a solar flare off the southwest limb of the disk at totality. Many people reported seeing the same thing, which makes us a bit jealous — OK, a lot jealous. Of course, this presented an opportunity to the “Well, ackchyually” crowd to point out that there were no solar flares or coronal mass ejections at the time, so what people saw wasn’t an exquisitely timed and well-positioned solar flare but rather a well-timed and exquisitely positioned solar prominence. Glad we cleared that up. Either way, people in the path of totality saw the Sun belching out gigatons of plasma while we had to settle for 27% totality.

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Lamp Becomes Rotating, Illuminated Sign For Festival Table

April 2, 2024 by Donald Papp 5 Comments

Two things we love are economical solutions to problems, and clever ways to use things for other than their intended purpose. [CelGenStudios] hits both bases with a simple illuminated and spinning sign made from a lamp and a couple economical pieces of hardware: an LED bulb, and a solar-powered product spinner. Both are readily and cheaply available from your favorite overseas source.

The first step in making a cheap illuminated sign is to not buy one, but instead make do with a standing lamp. Plug a bright LED bulb into the socket, decorate the lampshade with whatever logos or signs one wishes to display, and one has an economical illuminated sign suitable for jazzing up a table at an event. But what really kicks it up a notch is making it rotate, and to do that is where the clever bit comes in.

Mounting the lampshade to the solar turntable body yields a simple, rotating, illuminated sign.

The first attempt used a BBQ rotisserie motor to turn the whole lamp, but it was too loud and not especially stable. The second attempt used a “disco ball effect” LED bulb with a motorized top; it worked but turned too quickly and projected light upward instead of into the lampshade.

The winning combination is LED bulb plus a little solar-powered turntable onto which the lampshade mounts. As a result, the lampshade spins slowly when the lamp is turned on. It might not be the most durable thing to ever come out of a workshop, but as [CelGenStudios] says, it only needs to last for a weekend.

The basic concept is far more simple than it might sound, so check it out in the video (embedded below) to see it in action. Curious about what’s inside those little solar spinners? Skip to 5:55 in the video to see how they work. And if you’re intrigued by the idea of using solar power for motive force but want to get more hands-on with the electrical part, we have just the resource for turning tiny motors with tiny solar cells.

Thanks to [Bike Forever] for the tip!

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The PhotonPower Zero board laying on a desk surface

PhotonPower Zero For Effortless Solar Pi Zero Projects

April 2, 2024 by Arya Voronova 2 Comments

A Pi Zero doesn’t need much to sustain itself, and it’s projects like the PhotonPower Zero that remind us of it its low appetite when we need this reminder most. The PhotonPower Zero board lets you power a Pi Zero board from a solar cell, with a LiIon backup, and a microcontroller for power management. Created by [David Murray], this board’s been a perfect solution for quite a few projects of his, and now he is sharing the design so that we can create outdoor-suited devices as easily as he’s been able to.

Tested for months in Australian summer and winter conditions alike, the design pulls no punches and has everything you might need. Like any self-respecting power addon, it has a management microcontroller for going as low-power as you’d like, communicating the battery data to the Pi Zero, and being able to safely shut it down when needed. If you fancy what this board does, [David Murray] tells you all, both in the video and in the associated posts!

One of the best parts about this board is that it’s fully open-source – schematics, KiCad PCB source files, and even 3D designs are available in the GitHub repo. You could source all the parts right now and build a fleet of solar-powered Zeros, and if you want the hard parts to be done for you, there’s a Kickstarter campaign that lets you get a PhotonPower Zero board without self-assembly. We’ve covered similar boards before – powering a Pi Zero isn’t lost art, and, there’s a lot to learn from this project specifically. Such boards are especially tempting, given that the latest Pi Zero W 2 is the most efficient Pi Zero to date – outdoor-capable 24/7 powered devices with a fair bit of CPU have never been this close!

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Hackaday Links: March 31, 2024

March 31, 2024 by Dan Maloney 6 Comments

Battlelines are being drawn in Canada over the lowly Flipper Zero, a device seen by some as an existential threat to motor vehicle owners across the Great White North. The story started a month or so ago, when someone in the government floated the idea of banning devices that could be “used to steal vehicles by copying the wireless signals for remote keyless entry.” The Flipper Zero was singled out as an example of such a nefarious device, even though relatively few vehicles on the road today can be boosted using the simple replay attack that a Flipper is capable of, and the ones that are vulnerable to this attack aren’t all that desirable — apologies to the 1993 Camry, of course. With that threat hanging in the air, the folks over at Flipper Devices started a Change.org petition to educate people about the misperceptions surrounding the Flipper Zero’s capabilities, and to urge the Canadian government to reconsider their position on devices intended to explore the RF spectrum. That last bit is important, since transmit-capable SDR devices like the HackRF could fall afoul of a broad interpretation of the proposed ban; heck, even a receive-only SDR dongle might be construed as a restricted device. We’re generally not much for petitions, but this case might represent an exception. “First they came for the Flipper Zero, but I did nothing because I don’t have a Flipper Zero…”

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Stacking Solar Cells Is A Neat Trick To Maximise Efficiency

March 7, 2024 by Lewin Day 51 Comments

Solar power is already cheap and effective, and it’s taking on a larger role in supplying energy needs all over the world. The thing about humanity, though, is that we always want more! Too much, you say? It’s never enough!

The problem is that the sun only outputs so much energy per unit of area on Earth, and solar cells can only be so efficient thanks to some fundamental physical limits. However, there’s a way to get around that—with the magic of tandem solar cells!

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Making A Dye-Sensitized Solar Cell Is Almost DIY-able

February 28, 2024 by Lewin Day 9 Comments

We see plenty of solar projects here on Hackaday, but they primarily consist of projects that use an off-the-shelf solar panel to power something else. We see very few projects where people actually create their own solar panels. And yet, that’s precisely what [Shih Wei Chieh] has done!

The project consists of a large dye-sensitized solar panel. These are a type of solar panel that can easily be created by the DIY builder, though their efficiency leaves something to be desired versus the best commercial types available. However, you can build them in any way you like to suit your application, which can have some potential benefits.

It consists of two pieces of FTO glass that is etched and prepared to become the electrodes for a string of solar cells. The cells have to be treated with titanium dioxide and then laced with silver traces, before being assembled with liquid electrolyte squirted in between. It’s finicky stuff, but the video almost makes it look easy… if you’re familiar with working in a chemistry lab, that is.

While it’s DIY-able, it’s at the outer edge of what some of us would be comfortable with. It does involve some steps with semi-obscure chemicals and the use of a kiln to produce the cells. The design shown here outputs around 5.8 volts and 51 milliamps. It’s not heaps, but it’s enough to run a low-power project for some time in an area with decent sun.

We’ve seen some other great solar projects over the years, too! Video after the break.

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