See Satellites In Broad Daylight With This Sky-Mapping Dish Antenna

If you look up at the night sky in a dark enough place, with enough patience you’re almost sure to see a satellite cross the sky. It’s pretty cool to think you’re watching light reflect off a hunk of metal zipping around the Earth fast enough to never hit it. Unfortunately, it doesn’t work during the daylight hours, and you really only get to see satellites in low orbits.

Thankfully, there’s a trick that allows you to see satellites any time of day, even the ones in geosynchronous orbits — you just need to look using microwaves. That’s what [Gabe] at [saveitforparts] did with a repurposed portable satellite dish, the kind that people who really don’t like being without their satellite TV programming when they’re away from home buy and quickly sell when they realize that toting a satellite dish around is both expensive and embarrassing. They can be had for a song, and contain pretty much everything needed for satellite comms in one package: a small dish on a motorized altazimuth mount, a low-noise block amplifier (LNB), and a single-board computer that exposes a Linux shell.

After figuring out how to command the dish to specific coordinates and read the signal strength of the received transponder signals, [Gabe] was able to cobble together a Python program to automate the task. The data from these sweeps of the sky resulted in heat maps that showed a clear arc of geosynchronous satellites across the southern sky. It’s quite similar to something that [Justin] from Thought Emporium did a while back, albeit in a much more compact and portable package. The video below has full details.

[Gabe] also tried turning the dish away from the satellites and seeing what his house looks like bathed in microwaves reflected from the satellite constellation, which worked surprisingly well — well enough that we’ll be trawling the secondary market for one of these dishes; they look like a ton of fun.

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Move Aside Yoda, It’s Furby’s Turn On Luke’s Back

When you want a backpack that turns heads and gets people talking, you can get ahead of the conversation with a talking backpack. [Nina] created a rucksack with the legendary babbler itself, the infamous Furby.

Believe it or not, no actual Furbies were sacrificed in the making of this backpack. The build uses an Arduino Nano, two servos, and a DFPlayer Mini for audio. A 3D printed faceplate is used for the iconic eyes and face. The code is fairly simple, waiting for a random delay and then triggering one of four effects. It can play a sound or blink and does its best to move the mouth while the sound is playing thanks to the handy busy line coming off the sound module. A unicorn children’s backpack offered a furry shell to stuff the electronics inside. A custom PCB makes the whole thing just a little neater internally.

Perhaps next [Nina] can integrate voice recognition so that the backpack can answer simple questions like an Alexa-powered Furby we’ve seen before.

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Why A Community Hackerspace Should Be A Vital Part Of Being An Engineering Student

Travelling the continent’s hackerspaces over the years, I have visited quite a few spaces located in university towns. They share a depressingly common theme, of a community hackerspace full of former students who are now technology professionals, sharing a city with a university anxious to own all the things in the technology space and actively sabotaging the things they don’t own. I’ve seen spaces made homeless by university expansion, I’ve seen universities purposefully align their own events to clash with a hackerspace open night and discourage students from joining, and in one particularly egregious instance, I’ve even seen a university take legal action against a space because they used the name of the city, also that of the university, in the name of their hackerspace. I will not mince my words here; while the former are sharp practices, the latter is truly disgusting behaviour.

The above is probably a natural extension of the relationship many universities have with their cities, which seems depressingly often to be one of othering and exclusion. Yet in the case of hackerspaces I can’t escape the conclusion that a huge opportunity is being missed for universities to connect engineering and other tech-inclined students with their alumni, enhance their real-world skills, and provide them with valuable connections to tech careers.

Yesterday I was at an event organised by my alma mater, part of a group of alumni talking to them about our careers.  At the event I was speaking alongside an array of people with varying careers probably more glittering than mine, but one thing that came through was that this was something of a rare opportunity for many of the students, to talk to someone outside the university bubble. Yet here were a group of engineers, many of whom had interesting careers based locally, and in cases were even actively hiring. If only there were a place where these two groups could informally meet and get to know each other, a community based on a shared interest in technology, perhaps?

It’s not as though universities haven’t tried on the hackerspace front, but I’m sad to say that when they fill a room with cool machines for the students they’re rather missing the point. In some of the cases I mentioned above the desire to own all the things with their own students-only hackerspace was the thing that led to the community hackerspaces being sabotaged. Attractive as they are, there’s an important ingredient missing, they come from a belief that a hackerspace is about its facilities rather than its community. If you were to look at a room full of brand-new machines and compare it with a similar room containing a temperamental Chinese laser cutter and a pair of battered 3D printers, but alongside a group of seasoned engineers in an informal setting, which would you consider to be of more benefit to a student engineer? It should not be a difficult conclusion to make.

Universities value their local tech industry, particularly that which has some connection to your university. You want your students to connect with your alumni, to connect with the local tech scene, and to ultimately find employment within it. At the same time though, you’re a university, you see yourselves as the thought leader, and you want to own all the things. My point is that these two positions are largely incompatible when it comes to connecting your engineering students with the community of engineers that surround you, and you’re failing your students in doing so.

Thus I have a radical proposal for universities. Instead of putting all your resources on a sterile room full of machines for your students, how about spending a little into placing them in a less shiny room full of professional engineers on their off-time? Your local hackerspace is no threat to you, instead it’s a priceless resource, so encourage your students to join it. Subsidise them if they can’t afford the monthly membership, the cost is peanuts compared to the benefit. Above all though, don’t try to own the hackerspace, or we’re back to the first paragraph. Just sometimes, good things can happen in a town without the university being involved.

Hackaday Podcast 212: Staring Through ICs, Reading Bloom Filters, And Repairing, Reworking, And Reballing

It was quite the cornucopia of goodness this week as Elliot and Dan sat down to hash over the week in hardware hacking. We started with the exciting news that the Hackaday Prize is back — already? — for the tenth year running! The first round, Re-Engineering Education, is underway now, and we’re already seeing some cool entries come in. The Prize was announced at Hackday Berlin, about which Elliot waxed a bit too. Speaking of wax, if you’re looking to waterproof your circuits, that’s just one of many coatings you might try. If you’re diagnosing a problem with a chip, a cheap camera can give your microscope IR vision. Then again, you might just use your Mark I peepers to decode a ROM. Is your FDM filament on the wrong spool? We’ve got an all-mechanical solution for that. We’ll talk about tools of the camera operator’s trade, the right to repair in Europe, Korean-style toasty toes, BGA basics, and learn just what the heck a bloom filter is — or is it a Bloom filter?

Check out the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!

Download your own personal copy!

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GaN Charger Teardown Reveals Value Of This New Technology

Every so often, a new technology comes along that offers a broad range of benefits over what we already have. Just as lithium-ion batteries have made nickel-cadmium cells boring and old hat, gallium nitride semiconductors are making silicon parts look unimpressive by comparison. [Brian Dipert] looked at what this means in a practical sense by tearing down a GaN phone charger.

The charger in question is a 30 watt USB-C charger produced by Voltme. It cost [Brian] just $10, as prices of GaN hardware have come down significantly as economies of scale have kicked in. The charger measures just 1.2×1.3×1.2 inches, and weighs only 1.5 ounces. That compact size is thanks to GaN semiconductors, which are able to run cooler at higher power levels than their silicon forebearers.

Cracking into the charger required levering open the case. The back panel came off with some work, revealing the mains terminals, which deliver AC power to the PCB inside via the case holding them in contact. Interestingly, the entire circuit inside is filled with an adhesive thermal goop, which helps pass heat from the hottest components to the charger’s case. [Brian] is able to guide us through the circuit, and he identified many of the major components. However, some of the markings on chips were beyond his research skills, and he asks any knowing readers to contribute their own information.

It’s interesting to see just what makes the high-powered compact chargers of today tick. Plus, it’s a hallmark of progress that what was once considered a wonder material can now be had in a $10 commodity phone charger from Amazon. How times change!

This Week In Security: Macstealer, 3CX Carnage, And Github’s Lost Key

There’s a naming overload here, as two bits of security news this week are using the “MacStealer” moniker. We’re first going to talk about the WiFi vulnerability, also known as Framing Frames (pdf). The WPA encryption schemes introduced pairwise encryption, ensuring that not even other authenticated users can sniff each others’ traffic. At least that’s the idea, but this attack finds a couple techniques to bypass that protection.

A bit more background, there are a couple ways that packets can be delayed at the sender side. One of those is the power-save message, that signals the access point that the given client is going into a low power state. “Hold my calls, I’m going to sleep.” That message is a single bit in a frame header. And notably, that bit isn’t covered by WPA encryption or verification. An attacker can send a message, spoof a victim’s MAC address, and the access point marks that client as being in power-save mode.

This observation leads to a question: What happens when the encryption details change between the packet joining the queue, and actually transmitting? Turns out, the specifications on WiFi encryption don’t spell it out, and some implementations do the last thing you’d want, like sending the packets in the clear. Whoops. This behavior was the case in the Linux kernel through version 5.5.0, but starting with 5.6.0, the buffered packets were simply dropped when the encryption key was unavailable. Continue reading “This Week In Security: Macstealer, 3CX Carnage, And Github’s Lost Key”

Archiving The Entirety Of DPReview Before It’s Gone

Despite the popular adage about everything on the internet being there forever, every day pages of information and sometimes entire websites are lost to the sands of time. With the imminent shutdown of the DPReview website, nearly 25 years of reviews and specifications of cameras and related content are at risk of vanishing. Also lost will be the content of forum posts, which can still be requested from DPReview staff until April 6th. All because the owner of the site, Amazon, is looking to cut costs.

As announced on r/photography, the Archive.org team is busy trying to download as much of the site as possible, but due to bottlenecks may not finish in time. One way around these bottlenecks is what is called the Archive Team Warrior, which involves either a virtual machine or Docker image that runs on distributed systems. In early April an archiving run using these distributed systems is planned, in a last-ditch attempt to retain as much of the  decades of content.

The thus archived content will be made available in the WARC (Web ARChive) format, in order to retain as much information as possible, including meta data and different versions of content.