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Hackaday Links: June 28, 2020

You can imagine how stressful life is for high-power CEOs of billion-dollar companies in these trying times; one is tempted to shed a tear for them as they jet around the world and plan their next big move. But now someone has gone and upset the applecart by coming up with a way to track executive private jets as they travel across North America. This may sound trivial, but then you realize that hedge fund managers pay big money for the exact same data in order to get an idea of who is meeting with whom and possibly get an idea of upcoming mergers and acquisitions. It’s also not easy, as the elites go to great lengths to guard their privacy. Luckily, the OpenSky Network lists all ADS-B traffic its web of ground stations receives, unlike other flight monitoring sites which weed out “sensitive” traffic. Python programs scrape the OpenSky API and cross-reference plane registrations with the FAA database to see which company jets are doing what. There are plenty of trips to Aspen and Jackson Hole to filter out, but with everyone and his little brother fancying themselves a day trader lately, it’s another tool in the toolbox.

We got a nice note from Michelle Thompson this week thanking us for mentioning the GNU Radio Conference in last week’s Links article, and in particular for mentioning the virtual CTF challenge that they’re planning. It turns out that Michelle is deeply involved in designing the virtual CTF challenge, after having worked on the IRL challenges at previous conferences. She shared a few details of how the conference team made the decision to go forward with the virtual challenge, inspired in part by the success of the Hack-A-Sat qualifying rounds, which were also held remotely. It sounds like the GNU Radio CTF challenge will be pretty amazing, with IQ files being distributed to participants in lieu of actually setting up receivers. We wish Michelle and the other challenge coordinators the best of luck with the virtual con, and we really hope a Hackaday reader wins.

Amateur radio is often derided as a hobby, earning the epithet “Discord for Boomers” according to my son. There’s more than a grain of truth to that, but there are actually plenty of examples where a ham radio operator has been able to make a big difference in an emergency. Case in point is this story from the Western Massachusetts ARRL. Alden Jones (KC1JWR) was hiking along a section of the Appalachian Trail in southern Vermont last week when he suddenly got light-headed and collapsed. A passing hiker who happened to be an emergency medical technician rendered aid and attempt to contact 911 on his cell phone, but coverage was spotty and the dispatcher couldn’t hear him. So Alden, by this point feeling a little better, pulled out his handy talkie and made an emergency call to the local repeater. Luckily the Western Massachusetts Traffic Net was just about to start, so they went into emergency mode and coordinated the response. One of the hams even went to the rescue staging area and rigged up a quick antenna to improve the signal so that rescuers could finally get a helicopter to give Alden a ride to the hospital. He’s fine now, and hats off to everyone who pitched in on the eight-hour rescue effort.

And finally, there are obviously a lot of details to be worked out before anyone is going to set foot on the Moon again. We’ve got Top People™ working on all the big questions, of course, but apparently NASA needs a little help figuring out how and where the next men and first women on the Moon are going to do their business. The Lunar Loo Challenge seeks innovative designs for toilets that can be used in both microgravity and on the lunar surface. There is $35,000 in prize money for entrants in the Technical division; NASA is also accepting entries in a Junior division, which could prove to be highly entertaining.

Turn An Unused Pi Zero Into A Parts Bin WiFi Extender

We know a lot of you are sitting on an unused Raspberry Pi Zero W, maybe even several of them. The things are just too small and cheap not to buy in bulk when the opportunity presents itself. Unfortunately, the Zero isn’t exactly a powerhouse, and it can sometimes be tricky to find an application that really fits the hardware.

Which is why this tip from [Tejas Lotlikar] is worth taking a look at. Using the Pi Zero W, a cheap USB WiFi adapter, and some software trickery, you can put together a cheap extender for your wireless network. The Pi should even have a few cycles left over to run ad-blocking software like Pi-hole while it shuffles your packets around the tubes.

[Tejas] explains every step of the process, from putting the Raspbian image onto an SD card to convincing wpa_supplicant to put the Pi’s WiFi radio into Access Point mode. Incidentally, this means that you don’t need to be very selective about the make and model of the USB wireless adapter. Something with an external antenna is preferable since it will be able to pull in the weak source signal, but you don’t have to worry about it supporting Soft AP.

With the software configured, all you need to finish this project off is an enclosure. A custom 3D printed case large enough to hold both the Pi and the external WiFi adapter would be a nice touch.

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Hackaday Links: February 23, 2020

If you think your data rates suck, take pity on New Horizons. The space probe, which gave us lovely pictures of the hapless one-time planet Pluto after its 2015 flyby, continued to plunge and explore other, smaller objects in the Kuiper belt. In January of 2019, New Horizons zipped by Kuiper belt object Arrokoth and buffered its findings on the spacecraft’s solid-state data recorders. The probe has been dribbling data back to Earth ever since at the rate of 1 to 2 kilobits per second, and now we have enough of that data to piece together a story of how planets may have formed in the early solar system. The planetary science is fascinating, but for our money, getting a probe to narrowly miss a 35-kilometer long object at a range of 6.5 billion km all while traveling at 51,500 km/h is pretty impressive. And if as expected it takes until September to retrieve all the data from the event at a speed worse than dialup rates, it’ll be worth the wait.

Speaking of space, if you’re at all interested in big data, you might want to consider putting your skills to work in the search for extraterrestrial intelligence. The Berkeley SETI Research Center has been feeding data from the Green Bank Telescope and their Automated Planet Finder into the public archive of Breakthrough Listen, a 10-year, $100 million initiative to scan the million closest stars in our galaxy as well as the 100 nearest galaxies for signs of intelligent life. They’re asking for help to analyze the torrents of data they’re accumulating, specifically by developing software and algorithms to process the data. They’ve set up a site to walk you through the basics and get you started. If you’re handy with Python and have an interest in astronomy, you should check it out.

Staying with the space theme, what’s the best way to get kids interested in space and electronics? Why, by launching a satellite designed to meme its way across the heavens, of course. The Mission for Education and Multimedia Engagement satellite, or MEMESat-1, is being planned for a February 2021 launch. The 1U cubesat will serve as an amateur radio repeater and slow-scan TV (SSTV) beacon that will beam down memes donated to the project and stored on radiation-hardened flash storage. In all seriousness, this seems like a great way to engage the generation that elevated the meme to a modern art form in a STEM project they might otherwise show little interest in.

It looks as though Linux might be getting a big boost as the government of South Korea announced that they’re switching 3.3 million PCs from Windows to Linux. It’s tempting to blame Microsoft’s recent dropping of Windows 7 support for the defenestration, but this sounds like a plan that’s been in the works for a while. No official word on which distro will be selected for the 780 billion won ($655 million) effort, which is said to be driven by ballooning software license costs and a desire to get out from under Microsoft’s thumb.

And finally, in perhaps the ickiest auction ever held, the “Davos Collection” headed to the auction block this week in New York. The items offered were all collected from the 2018 World Economic Forum in Davos, Switzerland, where the world’s elites gather to determine the fate of the 99.999%. Every item in the collection, ranging from utensils and glassware used at the many lavish meals to “sanitary items” disposed of by the billionaires, and even hair and fluid samples swabbed from restrooms, potentially holds a genetic treasure trove in the form of the DNA it takes to be in the elite. Or at least that’s the theory. There’s a whole “Boys from Brazil” vibe here that we find disquieting, and we flatly refuse to see how an auction where a used paper cup is offered for $8,000 went, but if you’d like to virtually browse through the ostensibly valuable trash of oligarchs, check out the auction catalog.

Simple, Self-Contained LoRa Repeater In About An Hour

[Dave Akerman]’s interest in high-altitude projects means he is no stranger to long-range wireless communications, for which LoRa is amazingly useful. LoRa is a method of transmitting at relatively low data rates with low power over long distances.

Despite LoRa’s long range, sometimes the transmissions of a device (like a balloon’s landed payload) cannot be received directly because it is too far away, or hidden behind buildings and geography. In these cases a useful solution is [Dave]’s self-contained LoRa repeater. The repeater hardware is simple, and [Dave] says that if one has the parts on hand, it can be built in about an hour.

The device simply re-transmits any telemetry packets it receives, and all that takes is an Arduino Mini Pro and a small LoRa module. A tiny DC-DC converter, battery, and battery charger rounds out the bill of materials to create a small and self-contained unit that can be raised up on a mast, flown on a kite, or carried by a drone.

The repeater’s frequency and other settings can even be reprogrammed (using a small windows program) for maximum flexibility, making the little device invaluable when going hunting for landed payloads like the one [Dave] used to re-create a famous NASA image using a plastic model and a high-altitude balloon. Check out the details on the GitHub repository for the project and start mashing “add to cart” for parts at your favorite reseller.

The $50 Ham: Checking Out The Local Repeater Scene

So far in this series, we’ve covered the absolute basics of getting on the air as a radio amateur – getting licensed, and getting a transceiver. Both have been very low-cost exercises, at least in terms of wallet impact. Passing the test is only a matter of spending the time to study and perhaps shelling out a nominal fee, and a handy-talkie transceiver for the 2-meter and 70-centimeter ham bands can be had for well under $50. If you’re playing along at home, you haven’t really invested much yet.

The total won’t go up much this week, if at all. This time we’re going to talk about what to actually do with your new privileges. The first step for most Technician-class amateur radio operators is checking out the local repeaters, most of which are set up exactly for the bands that Techs have access to. We’ll cover what exactly repeaters are, what they’re used for, and how to go about keying up for the first time to talk to your fellow hams.

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Es’hail-2: Hams Get Their First Geosynchronous Repeater

In the radio business, getting the high ground is key to covering as much territory from as few installations as possible. Anything that has a high profile, from a big municipal water tank to a roadside billboard to a remote hilltop, will likely be bristling with antennas, and different services compete for the best spots to locate their antennas. Amateur radio clubs will be there too, looking for space to locate their repeaters, which allow hams to use low-power mobile and handheld radios to make contact over a vastly greater range than they could otherwise.

Now some hams have claimed the highest of high ground for their repeater: space. For the first time, an amateur radio repeater has gone to space aboard a geosynchronous satellite, giving hams the ability to link up over a third of the globe. It’s a huge development, and while it takes some effort to use this new space-based radio, it’s a game changer in the amateur radio community.

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The WiFi Repeater You Probably Have On Your Bench

Few things are as frustrating as a WiFi signal that drops in and out. On a public network it is bad enough but at home? Even if you can live with it, your cohabitants will certainly impune your technical abilities if they don’t have solid WiFi.  One solution is a WiFi repeater. You can buy one, of course. But you can also make one out of an ESP8266 and some code from GitHub. There is also a video about the project, below.

[Martin Ger’s] code implements NAT, so it isn’t a true WiFi repeater, but more of a bridge or router. Of course, that means performance isn’t stellar, but tests show it can sustain about 5 Mbps, which isn’t bad for a little board that costs a couple of bucks. There is a limit of 8 clients, but that’s more than enough for a lot of cases. Even if you don’t want to use it as a router, it has a mesh mode that could be a basis for some interesting projects all by itself.

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