19 Coils Make Charging Wireless

June 20, 2021 by 49 Comments

Wireless charging is conceptually simple. Two coils form an ad hoc transformer with the primary in the charger and the secondary in the charging device. However, if you’ve ever had a wireless charging device, you know that reality can be a bit more challenging since the device must be positioned just so on the charger. Xiaomi has a multi-coil charger that can charge multiple devices and is tolerant of their positioning on the charger. How does it work? [Charger Lab] tears one apart and finds 19 coils and a lot of heat management crammed into the device.

The first part of the post is a terse consumer review of the device, looking at its dimensions and features. But the second part is when the cover comes off. The graphite heat shield looks decidedly like an accidental spill of something, but we’re sure that’s just how it appears. The coils are packed in tight in three layers. We have to wonder about their mutual interactions, and we assume that only some of them are active at any given time. The teardown shows a lot of the components and even pulls datasheets on many components, but doesn’t really go into the theory of operation.

Still, this is an unusual device to see from the inside. It is impressive to see so much power and thermal management in such a tiny package. We wonder that we don’t see more wireless charging in do-it-yourself projects. We do see some, of course. Not to mention grafting a charging receiver to an existing cell phone.

Compact M&M Sorter Goes Anywhere

June 20, 2021 by 11 Comments

Let’s face it — eating different colored candy like M&Ms or Skittles is just a little more fun if you sort your pile by color first. The not-fun part is having to do it by hand. [Jackofalltrades_] decided to tackle this time-worn problem for engineering class because it’s awesome and it satisfies the project’s requirement for sensing, actuation, and autonomous sequencing. We’d venture to guess that it satisfies [Jackofalltrades_]’ need for chocolate, too.

Here’s how it works: one by one, M&Ms are selected, pulled into a dark chamber for color inspection, and then dispensed into the proper cubby based on the result. [Jackofalltrades_] lived up to their handle and built a color-detecting setup out of an RGB LED and light-dependent resistor. The RGB LED shines red, then, green, then blue at full brightness, and takes a voltage reading from the photocell to figure out the candy’s color. At the beginning, the machine needs one of each color to read in and store as references. Then it can sort the whole bag, comparing each M&M to the reference values and updating them with each new M&M to create a sort of rolling average.

We love the beautiful and compact design of this machine, which was built to maximize the 3D printer as one of the few available tools. The mechanical design is particularly elegant. It cleverly uses stepper-driven rotation and only needs one part to do most of the entire process of isolating each one, passing it into the darkness chamber for color inspection, and then dispensing it into the right section of the jar below. Be sure to check out the demo after the break.

Need a next-level sorter? Here’s one that locates and separates the holy grail of candy-coated chocolate — peanut M&Ms that didn’t get a peanut.

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A Mini USB Display For Your PC Desktop

June 20, 2021 by 16 Comments

By now it’s likely that most Hackaday readers will be used to USB display adapters, in their most common form channeling DisplayPort over the ubiquitous serial interface. Connecting to projectors and other screens with a laptop becomes a breeze, and gone are the days of “Will my laptop work in the venue” stress for people delivering presentations. [Avra Mitra]’s STM32 tiny monitor may not ascend to these giddy heights, but it does at least live up to the promise of reproducing a desktop onto a small colour LCD hooked up through a USB port.

Not through any DisplayPort wizardry though, instead it relies on a Python script that takes successive screen grabs and streams them through USB to the microcontroller, which in tun puts them on the display. It’s claimed to achieve 6 to 7 frames per second as you can see in the video below, with an admission that there remains a huge scope for improvement.

Notwithstanding its limited utility at the moment, we can see that maybe this idea could have its uses in a very basic display after a few improvements. Meanwhile, more conventional monitors take the established route of pairing a dedicated controller board with an LCD panel.

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Apollo Shift Register Is Discrete

June 19, 2021 by 9 Comments

We’re unabashed fans of [Ken Shirriff] here at Hackaday, and his latest post about an Apollo-era transistorized shift register doesn’t disappoint. Of course, nowadays a 16-bit shift register is nothing special. But in 1965, this piece of Apollo test hardware weighed five pounds and likely cost at least one engineer’s salary in the day, if not more.

The incredible complexity of the the Apollo spacecraft required NASA to develop a sophisticated digital system that would allow remote operators to execute tests and examine results from control rooms miles away from the launch pad.

This “Computer Buffer Unit” was used to hold commands for the main computer since a remote operator could not use the DSKY to enter commands directly. Externally the box looks like a piece of military hardware, and on the inside has six circuit boards stacked like the pages of a book. To combat Florida’s notoriously damp conditions, the enclosure included a desiccant bag and a way to fill the device with nitrogen. A humidity indicator warned when it was time to change the bag.

There is a lot more in the post, so if you are interested in unusual construction techniques that were probably the precursor to integrated circuits, diode transistor logic, or just think old space hardware is cool, you’ll enjoy a peek inside this unusual piece of gear. Be sure to check out some of [Ken]’s previous examinations, from tiny circuits to big computers.

Turning GameCube & N64 Pads Into MIDI Controllers

June 19, 2021 by 2 Comments

It’s fair to say that the Nintendo 64 and GameCube both had the most unique controllers of their respective console generations. The latter’s gamepads are still in high demand today as the Smash Bros. community continues to favor its traditional control scheme. However, both controllers can easily be repurposed for musical means, thanks to work by [po8aster].

The project comes in two forms – the GC MIDI Controller and the N64 MIDI Controller, respectively. Each uses an Arduino Pro Micro to run the show, a logic level converter, and [NicoHood’s] Nintendo library to communicate with the controllers. From there, controller inputs are mapped to MIDI signals, and pumped out over traditional or USB MIDI.

Both versions come complete with a synth mode and drum mode, in order to allow the user to effectively play melodies or percussion. There’s also a special mapping for playing drums using the Donkey Konga Bongo controller with the GameCube version. For those eager to buy a working unit rather than building their own, they’re available for purchase on [po8aster’s] website.

It’s a fun repurposing of video game hardware to musical ends, and we’re sure there’s a few chiptune bands out there that would love to perform with such a setup. We’ve seen other great MIDI hacks on Nintendo hardware before, from the circuit-bent SNES visualizer to the MIDI synthesizer Game Boy Advance. Video after the break.

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IPod HiFi Gains New High Notes

June 19, 2021 by No comments

The iPod HiFi was a stereo speaker add-on produced by Apple in the mid-2000s for their iPod range, a $300-plus speaker cabinet with twin drivers per channel, an iPod dock, aux, and TOSLINK interfaces. It’s caught the eye of [Jake], in particular one posted on Reddit that had an extra set of tweeters to improve the HiFi’s lackluster treble. The question was that it might have been an Apple prototype, but lacking his own [Jake] set out to replicate it.

The job he’s done is to a high quality. The baffle has first 3D scanned, and then recesses were milled out of it so the tweeters could be press-fit in. He’s driving them through a simple LC crossover circuit taken from the speaker drive, and reports himself happy with the result.

Unfortunately, we still don’t know whether or not the Reddit original was an Apple prototype or not. We’d be inclined to say it isn’t and praise the skills of the modder who put the tweeters in, but in case it might be we’d point to something that could deliver some clues. The iPod HiFi didn’t use a passive crossover, instead it had a DSP and active crossover, driving four class D amplifiers. If you find one with tweeters and they’re driven from the DSP through an extra pair of amplifiers then put it on eBay as a “RARE BARN FIND APPLE PROTOTYPE!” and make a fortune, otherwise simply sit back and enjoy the extra treble a previous owner gave it.

Of course, some people baulked at the price tag of the Apple speaker, and made their own.

1700 Regulatory Approvals Revoked In South Korea

June 19, 2021 by 38 Comments

For the first time since its inception, the Korea Communications Commission this week revoked the regulatory approvals of 1,696 telecommunications devices from 378 companies, both foreign and domestic. Those companies must recall unsold inventory from the shelves, and prove conformity of existing products already sold. In addition, the companies may not submit new applications for these items for one year. It’s not clear what would happen to already-sold equipment if the manufacturer is unable to prove conformity as requested — perhaps a recall? Caught up in this are CCTV products, networking equipment, Bluetooth speakers, and drones from companies like Huawei, DJI, and even Samsung.

The heart of the issue are what’s known as Mutual Recognition Agreements (MRAs) between countries to officially recognize of each other’s certification testing laboratories (or Conformity Assessment Bodies, CAB, in the lingo of the industry). Currently ten countries (USA, Canada, Mexico, UK, Israel, Japan, Korea, Singapore, Vietnam, and Australia), the 27 member states of the EU, Taiwan and Hong Kong all have MRAs with each other. Based on these MRAs, a Korean manufacturer could have a product tested by a laboratory in Israel, for example, and all would be kosher with the KCC.

At the center of attention is the Bay Area Compliance Laboratories (BACL), established in 1996 and headquartered in Sunnyvale, California. BACL has laboratories all over the world (USA, Taiwan, Hong Kong, Vietnam, and mainland China). Except for those in mainland China, all BACL laboratories are acceptable per the MRAs. The KCC received a tip last year that some compliance test reports for some products might be defective.

A six-month investigation in cooperation with the US National Institute of Standards and Technology (NIST) resulted in the announcement this week. Korean companies, 378 of them to be exact, had submitted test reports from BACL Sunnyvale which appeared to be appropriate. But on further investigation, it was learned that the actual testing was done by BACL laboratories in mainland China and only the reports were prepared in Sunnyvale.

It’s not clear whether these companies were knowingly playing fast and loose with the rules, whether BACL was complicit, if it was just a misunderstanding of the intricacies of the regulations and MRAs, or a combination of all three. Regardless, the KCC said that intent doesn’t matter according the their rules. It also has not been suggested that the products themselves are problematic, nor has anyone suggested that BACL’s Chinese laboratories performed slipshod work — rather, the KCC says it has no choice but to proceed with the revocation based on the applicable laws.