Antenna Mount Designed For On-The-Go SDR

December 16, 2022 by 15 Comments

Software-defined radio is all the rage these days, and for good reason. It eliminates or drastically reduces the amount of otherwise pricey equipment needed to transmit or even just receive, and can pack many more features than most affordable radio setups otherwise would have. It also makes it possible to go mobile much more easily. [Rostislav Persion] uses a laptop for on-the-go SDR activities, and designed this 3D printed antenna mount to make his radio adventures much easier.

The antenna mount is a small 3D printed enclosure for his NESDR Smart Dongle with a wide base to attach to the back of his laptop lid with Velcro so it can easily be removed or attached. This allows him to run a single USB cable to the dongle and have it oriented properly for maximum antenna effectiveness without something cumbersome like a dedicated antenna stand. [Rostislav] even modeled the entire assembly so that he could run a stress analysis on it, and from that data ended up filling it with epoxy to ensure maximum lifespan with minimal wear on the components.

We definitely appreciate the simple and clean build which allows easy access to HF and higher frequencies while mobile, especially since the 3D modeling takes it a step beyond simply printing a 3D accessory and hoping for the best. There’s even an improved version on his site here. To go even one step further, though, we’ve seen the antennas themselves get designed and then 3D printed directly.

A Simple High-Fidelity DIY Mic Pre Amp

December 16, 2022 by 13 Comments

If you’re doing any serious work with microphones, you’ll typically find yourself in want of a dedicated preamp. [ojg] needed just such a thing for acoustic measurement duties, and set about working up a cheap DIY design by the name of ThatMicPre.

The design is based around the THAT1510 preamp IC, known for its good frequency response and low harmonic distortion and noise. The design is also compatible with THAT1512, SSM2019, and INA217 chips as well. [ojg] gave the design switch-controlled gain levels, providing greater accuracy than a potentiometer adjustment, and the ability to supply phantom power for mics that require it. The PCB is designed to rely on through-hole parts and common connectors for easy assembly.

The design is open source, and has already been built by others on the DIYAudio forums. Built into a simple case, it looks like a handsome and well-built piece of audio equipment. We’ve featured quite a few unique preamps over the years, and if you’ve been building your own, we’d love to see those too!

Foot Pedal Ups Vim Productivity, Brings Ergonomic Benefits

December 16, 2022 by 53 Comments

Vim is the greatest or the worst text editor of all time, depending on the tribe you’re in. Either way, members of both camps can appreciate this build from [Chris Price], which uses a foot pedal to ease operations for the user.

The basic concept was to use a pedal to enable switching between normal and insert modes. In Vim’s predecessor, vi, switching modes was easy, with the ESC key located neatly by the Q on the keyboard of the ADM-3A terminal. On modern keyboards, though, it’s a pain, and so a foot pedal is a desirable solution. In the Vim world, it’s referred to as a “Vim clutch.”

The build used a cheap pedal switch sourced from eBay, into which a Raspberry Pi Pico was installed. The Pico was hooked up to the switch contacts, and programmed to act as a USB HID device. When the pedal is pressed down, the Pico sends an “i” keypress to enter Vim’s insert mode. Releasing the pedal has the Pico send a “ESC” keypress to return to normal mode.

Those that use Vim on a regular basis would likely appreciate the productivity improvements of such a device. Plus, there’s some ergonomic benefits to not having to strain one’s hand over to reach the ESC key. Of course, it’s an old-school solution, but there’s still something so compelling and next-level about having a foot pedal hooked up to one’s dev rig.

Battery Engineering Hack Chat Gets Charged Up

December 16, 2022 by 9 Comments

Turn the clock back a couple of decades, and the only time the average person would have given much thought to batteries was when the power would go out, and they suddenly needed to juice up their flashlight or portable radio.  But today, high-capacity batteries have become part and parcel to our increasingly digital lifestyle. In fact, there’s an excellent chance the device your reading this on is currently running on battery power, or at least, is capable of it.

So let’s get to know batteries better. What’s the chemical process that allows them to work? For that matter, what even is a battery in the first place?

It’s these questions, and more, that made up this week’s Battery Engineering Hack Chat with Dave Sopchak. Our last Hack Chat of 2022 ended up being one of the longest in recent memory, with the conversation starting over an hour before the scheduled kickoff and running another half hour beyond when emcee Dan Maloney officially made his closing remarks. Not bad for a topic that so often gets taken for granted.

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Hackaday Podcast 197: Decoding VHS, Engineering The TV Guardian, And Gitting Code Into Your ESP32s

December 16, 2022 by No comments

This week, Editor-in-Chief Elliot Williams and Assignments Editor Kristina Panos delighted in the aural qualities of Kristina’s brand new, real (read: XLR) microphone before embarking on creating a podcast highlighting the best of the previous week’s hacks.

This week in the news, NASA returned to the Moon with Artemis I, and this time, there are CubeSats involved. After that, it’s on to the What’s That Sound results show, marred by Kristina’s cheating scandal (listening ahead of time) and Elliot’s reading the filename aloud before we started recording. Finally, we move on to the hacks — they start with a trip to the 90s both sonically and visually, and end with a really nice alarm clock that’s decidedly 70s, and definitely Hackaday.

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!

And/or download it and listen offline.

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Motion-Activated Clock Only Lights Up On Command

December 16, 2022 by 8 Comments

While some of us can fall asleep anywhere from a noisy auditorium to a brightly lit train station, others are more fussy, requiring quiet and dark to nod off. [Craig Lindley] likes to minimize light when he’s trying to sleep, and decided to build himself a simple clock that wouldn’t disturb his rest.

The basic concept was to build a clock that would only display the time on command. In this case, that command would be a wave of a hand in front of the clock. The build is based around a Lilygo ESP32 T-Display unit, which combines the ESP32 with an LCD display and a battery management system. The ESP32’s WiFi connection provides accurate time via querying an NTP server. A passive infrared motion sensor is used to detect the motion of the user’s hand in front of the clock.

While all kinds of clocks and clock radios are available out there, few are motion activated. [Craig]’s work is a great demonstration of building your own solutions to your problems. We’ve seen some other neat motion-sensing convenience hacks before, too!

This Week In Security: Scamming The FBI, In The Wild, And AI Security

December 16, 2022 by 16 Comments

If you’re part of a government alphabet agency, particularly running a program to share information to fight cybercrime, make sure to properly verify the identity of new members before admission. Oh, and make sure the API is rate-limited so a malicious member can’t scrape the entire user database and sell it on a dark web forum.

Putting snark aside, this is exactly what has happened to the FBI’s InfraGuard program. A clever user applied to the program using a CEO’s name and phone number, and a convincing-looking email address. The program administrators didn’t do much due diligence, and approved the application. Awkward.

BSD Ping

First off, the good folks at FreeBSD have published some errata about the ping problem we talked about last week. First off, note that while ping does elevate to root privileges via setuid, those privileges are dropped before any data handling occurs. And ping on FreeBSD runs inside a Capsicum sandbox, a huge obstacle to system compromise from within ping. And finally, further examination of the bug in a real-world context casts doubt on the idea that Remote Code Execution (RCE) is actually possible due to stack layouts.

If someone messes up somewhere, go look if you messed up in the same or similar way somewhere else.

Sage advice from [Florian Obser], OpenBSD developer. So seeing the ping problem in FreeBSD, he set about checking the OpenBSD ping implementation for identical or similar problems. The vulnerable code isn’t shared between the versions, so he reached for afl++, a fuzzing tool with an impressive list of finds. Connect afl++ to the function in ping that handles incoming data, and see what shakes out. The conclusion? No crashes found in this particular effort, but several hangs were identified and fixed. And that is a win. Continue reading “This Week In Security: Scamming The FBI, In The Wild, And AI Security” →