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Build a web-connected software-defined receiver with OpenWebRX+ software, a Raspberry Pi, and an RTL-SDR USB stick. Explore and share the radio spectrum! Take one Raspberry Pi, an inexpensive Software-Defined Radio USB stick, and OpenWebRX+ software, and you have the makings of a powerful web-connected radio receiver. Listen to it on your mobile device, from anywhere in the world, and share your receiver online so that your friends can listen in as well. But that's not all: you can decode data transmissions of all kinds, and share that data too. Join an international community of radio enthusiasts exploring the hidden world of radio communications: aviation, ham radio, maritime, military, weather facsimile, digital modes, and more. The radio spectrum is out there for the taking-what are you waiting for? Turn your Raspberry Pi into a powerful, browser-based radio receiver, and discover the world of software-defined radio (SDR), one signal at a time. With just a Pi, an RTL-SDR dongle, and this book, you'll build a fully functional OpenWebRX+ web-connected radio receiver-no prior experience needed! You'll watch the airwaves spring to life with OpenWebRX+'s dynamic spectrum waterfall, a vibrant display of frequency, time, and signal strength that makes exploring the airwaves both visual and intuitive. Designed for curious beginners and experienced radio hobbyists alike, this hands-on guide walks you through every step: setting up your Raspberry Pi, installing OpenWebRX+ connecting your SDR hardware, and configuring your receiver to explore everything from AM/FM broadcasts to shortwave and amateur radio, and data transmissions everywhere. You'll learn about radio signals, where they lurk, the secrets they hold, and how to uncover them. The fun doesn't stop there: you can open your Open WebRX+ receiver to the world, so you and your friends can tune in on your mobile devices, from anywhere on the planet. Are you ready to surf the airwaves? Together, let's build something amazing! What You Need: You will need a copy of the free OpenWebRX+ software, and a computer to run it (we'll use a Raspberry Pi); an SD card and card writer; and SSH client software to communicate with the Pi. For the radio hardware, an inexpensive RTL-SDR dongle is a good start, though OpenWebRX+ supports other platforms. An antenna is essential: the type will depend on what you want to listen to, but an inexpensive VHF/UHF dipole kit will get you started, or even a long piece of wire.

Lint your docs like code: turn any style guide into enforceable rules with Vale and publish clear, consistent content every time.Create consistent content that gives readers confidence with Vale, the open-source prose linter that helps you enforce your style guide automatically. Use battle-tested rules based on freely available, popular style guides, apply your brand's terms with a custom vocabulary, and integrate Vale into your text editor, Git hooks, and CI pipeline. Catch typos and inclusive-language issues before they ship, and spend your energy on shaping ideas instead of fixing copy. Whether you're a technical writer working in a docs-as-code environment, or a software engineer who occasionally writes, you'll ship clean, consistent copy every time. When you work on a content project, keeping things consistent can feel impossible. Typos slip through, people don't follow style rules, and each contributor brings a slightly different voice. Vale helps you ensure consistency across your content. You'll start by catching typos as you learn how Vale works through hands-on examples. Then you'll bring in community rules based on Google's and Microsoft's style guides. You'll combine overlapping styles, adjust the rules to match your needs, and start shaping the experience you want readers to have. Then you'll build your own rules from scratch and create a custom vocabulary to teach Vale to enforce your team's voice and jargon. By the end, you'll have a fully integrated, reusable style package that works in your editor, GitHub Actions, and your build systems. And while this book uses Markdown in its examples, you'll be ready to apply everything you learned to reStructuredText, AsciiDoc, and even the comments in your source code. Vale gives you a fast, reliable, and customizable way to keep your content consistent. What You Need: This book uses Vale 3.12.0 or higher. You'll need a text editor like Visual Studio Code or Vim. You should be familiar with basic regular expressions, and be comfortable working with command-line tools and Markdown.