Building And Testing A Turbine Driven Hydro Generator

The theory behind hydropower is very simple: water obeys gravity and imparts the gained kinetic energy onto a turbine, which subsequently drives a generator.  The devil here is, of course, in all the details, as [FarmCraft101] on YouTube is in the process of finding out as he adds a small hydro plant to his farm dam. After previously doing all the digging and laying of pipe, in this installment, the goal is to build and test the turbine and generator section so that it can be installed.

The turbine section is 3D-printed and slides onto the metal shaft, which then protrudes from the back where it connects to a 230VAC, three-phase generator. This keeps it quite modular and easy to maintain, which, as it turns out, is a very good idea. After a lot of time spent on the lathe, cutting metal, and tapping threads, the assembled bulk of the system is finally installed for its first test run.

After all that work, the good news is that the 3D-printed turbine seems to work fine and holds up, producing a solid 440 RPM. This put it over the predicted 300 RPM, but that’s where the good news ends. Although the generator produces 28 watts, it’s officially rated for 3 kW at 300 RPM. Obviously, with the small size of this AliExpress-special, the expectation was closer to 750 watts, so that required a bit of investigation. As it turns out, at 300 RPM it only produces 9 watts, so obviously the generator was a dud despite cashing out $230 for it.

Hopefully, all it takes to fix this is to order a new generator to get this hydropower setup up and running. Fortunately, it seems that he’ll be getting his money back from the dud generator, so hopefully in the next video we’ll see the system cranking out something closer to a kilowatt of power.

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Nostalgic Camera Is A Mashup Of Analog Video Gear

These days, you get a fantastic camera with the purchase of just about any modern smartphone. [Abe] missed some of the charm of earlier, lower-quality digital cameras, though, and wanted to recreate that experience. The way forward was obvious. He built a nostalgic digital video camera from scratch!

[Abe] figured he could build the entire project around analog gear, and then simply find a way to store the video digitally, thus creating the effect he was looking for. To that end, the build is based around a small analog video camera that’s intended for use with FPV drones. It runs on 5 to 20 volts and outputs a simple composite video signal. This makes it easy to display its output on a small LCD screen, originally intended to be used with an automotive reversing camera. These were both paired with a mini video recorder module from RunCam, which can capture composite video and store it on a microSD card in 640 x 480 resolution.

These parts were quickly lashed together, with the camera sending its output to the RunCam video recorder module, which then passed it on to the screen. Everything worked as expected, so [Abe] moved on to implementing an on-screen display using the MAX7456 chip, which is built specifically for this purpose. It overlays text on the video feed to the screen as commanded by an RP2040 microcontroller. Once that was all working, [Abe] just had to provide a battery power supply and wrap everything up in a nice retro-styled case. Then, at the last minute, the separate camera and recorder modules were replaced by a TurboWing module that combined both into one.

The result is a nifty-looking camera that produces grainy, slurry, old-school digital video. If you love 640 x 480 as a resolution, you’ll dig this. It’s got strong 90s camcorder vibes, and that’s a very good thing.

We love a good custom camera around these parts, especially those that offer deliciously high resolution. If you’re building your own, be sure to let us know. Video after the break.

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Chip Swap Fixes A Dead Amiga 600

The Amiga 600 was in its day the machine nobody really wanted — a final attempt to flog the almost original spec 68000 platform from 1985, in 1992. Sure it had a PCMCIA slot nobody used, and an IDE interface for a laptop hard drive, but it served only to really annoy anyone who’d bought one when a few months later the higher-spec 1200 appeared. It’s had a rehabilitation in recent years though as a retrocomputer, and [LinuxJedi] has a 600 motherboard in need of some attention.

As expected for a machine of its age it can use replacement electrolytic capacitors, and its reset capacitor had bitten the dust. But there’s more to that with one of these machines, as capacitor leakage can damage the filter circuitry surrounding its video encoder chip. Since both video and audio flow through this circuit, there was no composite video to be seen.

The hack comes in removing the original chip rather than attempt the difficult task of replacing the filter, and replacing it with a different Sony chip in the same series. It’s nicely done with a connector in the original footprint, and a small daughterboard. The A600 lives again, but this time it won’t be a disappointment to anyone.

If you want to wallow in some Amiga history as well as read a rant about what went wrong, we have you covered.

Bare Metal STM32: Increasing The System Clock And Running Dhrystone

When you start an STM32 MCU with its default configuration, its CPU will tick along at a leisurely number of cycles on the order of 8 to 16 MHz, using the high-speed internal (HSI) clock source as a safe default to bootstrap from. After this phase, we are free to go wild with the system clock, as well as the various clock sources that are available beyond the HSI.

Increasing the system clock doesn’t just affect the CPU either, but also affects the MCU’s internal buses via its prescalers and with it the peripherals like timers on that bus. Hence it’s essential to understand the clock fabric of the target MCU. This article will focus on the general case of increasing the system clock on an STM32F103 MCU from the default to the maximum rated clock speed using the relevant registers, taking into account aspects like Flash wait states and the APB and AHB prescalers.

Although the Dhrystone benchmark is rather old-fashioned now, it’ll be used to demonstrate the difference that a faster CPU makes, as well as how complex accurately benchmarking is. Plus it’s just interesting to get an idea of how a lowly Cortex-M3 based MCU compares to a once top-of-the line Intel Pentium 90 CPU.

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Interactive Hopscotch Tiles Make The Game More Exciting

Hopscotch is a game usually played with painted lines or with the aid of a bit of chalk. However, if you desire fancier equipment, you might like the interactive hopscotch setup from [epatell].

The build uses yoga mats as the raw material to create each individual square of the hopscotch board. The squares all feature simple break-beam light sensors that detect when a foot lands in the given space. These sensors are monitored by a Raspberry Pi Pico in each square. In turn, the Pico lights up addressable NeoPixel LED strips in response to the current position of the player.

It’s a simple little project which makes a classic game just a little more fun. It’s also a great learning project if you’re trying to get to grips with things like microcontrollers and addressable LEDs in an educational context. We’d love to see the project taken a step further, perhaps with wirelessly-networked squares that can communicate and track the overall game state, or enable more advanced forms of play.

Meanwhile, if you’re working on updating traditional playground games with new technology, don’t hesitate to let us know!

Turn ‘Em On: Modern Nintendo Cartridges May Have A Limited Lifespan

Cartridge-based consoles have often been celebrated for their robust and reliable media. You put a simple ROM chip in a tough plastic housing, make sure the contacts are fit for purpose, and you should have a game cart that lasts for many decades.

When it comes to the Nintendo 3DS, though, there are some concerns that its carts aren’t up to snuff. Certain engineering choices were made that could mean these carts have a very limited lifespan, which could now be causing failures in the wild. It may not be the only Nintendo console to suffer this fate, either, thanks to the way modern cart-based consoles differ from their forebearers.

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Neutrino Transmutation Observed For The First Time

Once upon a time, transmutation of the elements was a really big deal. Alchemists drove their patrons near to bankruptcy chasing the philosopher’s stone to no avail, but at least we got chemistry out of it. Nowadays, anyone with a neutron source can do some spicy transmutation. Or, if you happen to have a twelve meter sphere of liquid scintillator two kilometers underground, you can just wait a few years and let neutrinos do it for you. That’s what apparently happened at SNO+, the experiment formally known as Sudbury Neutrino Observatory, as announced recently.

The scinillator already lights up when struck by neutrinos, much as the heavy water in the original SNO experiment did. It will also light up, with a different energy peak, if a nitrogen-13 atom happens to decay. Except there’s no nitrogen-13 in that tank — it has a half life of about 10 minutes. So whenever a the characteristic scintillation of a neutrino event is followed shortly by a N-13 decay flash, the logical conclusion is that some of the carbon-13 in the liquid scintillator has been transmuted to that particular isotope of nitrogen.

That’s not unexpected; it’s an interaction that’s accounted for in the models. We’ve just never seen it before, because, well. Neutrinos. They’re called “ghost particles” for a reason. Their interaction cross-section is absurdly low, so they are able to pass through matter completely unimpeded most of the time. That’s why the SNO was built 2 KM underground in Sudbury’s Creighton Mine: the neutrinos could reach it, but very few cosmic rays and no surface-level radiation can.  “Most of the time” is key here, though: with enough liquid scintillator — SNO+ has 780 tonnes of the stuff — eventually you’re bound to have some collisions.

Capturing this interaction was made even more difficult considering that it requires C-13, not the regular C-12 that the vast majority of the carbon in the scintillator fluid is made of. The abundance of carbon-13 is about 1%, which should hold for the stuff in SNO+ as well since no effort was made to enrich the detector. It’s no wonder that this discovery has taken a few years since SNO+ started in 2022 to gain statistical significance.

The full paper is on ArXiv, if you care to take a gander. We’ve reported on SNO+ before, like when they used pure water to detect reactor neutrinos while they were waiting for the scintillator to be ready. As impressive as it may be, it’s worth noting that SNO is no longer the largest neutrino detector of its kind.