I put a radio on the rack and now I listen to the world from a browser tab
A software defined radio receiver that lives on the network, sends nothing to anyone, and turns any screen in the house into a shortwave, airband, and scanner console. Here's the headless setup that made it boring to run.
Why headless, why now
I've had an RTL-SDR dongle kicking around for years. It's the twenty dollar USB stick that turned radios into a software problem instead of a soldering one. The catch was it always wanted a computer attached to it, and the computer wanted a monitor, and the monitor wanted me sitting in the same room as some coax nesting next to the router.
That's backwards. The radio should live where the rest of my gear lives, on the rack, quiet, no screen, and I should reach it from whatever laptop or phone I happen to be holding. That's what headless means here: the receiver has no desktop, just a small web server, and the browser is the whole front panel.
The tool that made it a service
The piece that ties it together is OpenWebRX. It wraps the SDR in a web interface you run as a background service, then serves the whole thing up as a page you can open on any device on your network. No app to install on the client, nothing to maintain on the host, just a server and a browser tab.
The part that sold me is that it's truly server side. The radio receives, the server processes, and the browser just plays the stream. That means low power devices like a phone or a tablet can drive the whole thing without breaking a sweat, because the heavy lifting never touches them.
What it listens to
The SDR itself covers a huge range, and OpenWebRX leans on that. With the right mode settings it'll pull in shortwave from across the world, pop over the ham bands, and catch airband chatter from nearby aircraft. You can sweep a wide swath on a waterfall display and jump the demodulator onto anything that looks alive.
The reason I actually stood mine up, though, was fire season. Out here that's a real part of the year, not a news story. So the frequency I care most about is the forest service and wildland firefighting nets, the ones the crews and the air attack use when a fire gets going. Being able to pull those up from a browser tab instead of hoping a scanner app somewhere has a feed of the right district is the whole ballgame for me.
When the smoke shows up on the horizon, I can listen in and get a sense of what's actually happening rather than trying to piece it together from a phone notification an hour late. The radio doesn't replace the official alert systems, it sits next to them, real time, on my terms, and it has already told me more about an active incident than any headline did.
You won't monitor every frequency at once, not practically. The dongle has limits and the antenna matters more than people like to admit. But you can sweep a wide swath on a waterfall display and jump the demodulator onto anything that looks alive. It's the difference between owning a radio and having a whole band of them in your pocket.
On the rack, not just on a desk
Two ways to host it, and both work fine. If you've got a virtualization setup like Proxmox, you spin up a small container or VM, pass the USB dongle through to it, install OpenWebRX, and let it ride. The USB passthrough is the one bit that needs to be right, but once the container can see the dongle the rest is plain sailing.
The other route is a Raspberry Pi sitting in a corner. Honestly the Pi is a great fit here, the whole stack sips power and the Pi is happy to sit there for months doing one job. You connect the dongle, put OpenWebRX on autostart, and forget about the box the way you want to forget about a good appliance.
The antenna secret nobody leads with
I'll save you the week I wasted. The antenna is half the system. Run a cheap telescoping whip out a window and you'll hear the strong stuff and little else. Get a proper antenna in a decent spot and suddenly the same dongle hears a world of difference. Before you sink money into radios, sink it into the thing that actually receives the signal.
What I'd do different
I'd buy a better antenna first and a second dongle second, because you will want to listen to two things at once the day after it's working. And I'd put it on the Pi behind all my normal network rules rather than leaving it wide open, because a radio on your network is still a box on your network, and it deserves the same treatment as the rest of the rack.