AntennaHead
macOS app

AntennaHead

A macOS app for software-defined-radio streaming. It tunes an RTL-SDR USB device, demodulates the signal, and serves audio plus a full control UI to any browser on your network.

You don't need an RTL-SDR radio for everything, though. Several functions work without one, especially on the Devices page: stream any Core Audio input (a microphone or line-in), have Text to Speech read .txt files from a folder through the audio pipeline, or open ControlBooth. An RTL-SDR radio is only needed to tune over-the-air stations.

Open the interactive UI → Source & build instructions Download v0.3.1-alpha (pre-release, .zip) →

What it does

Tune & demodulate

RTL-SDR wide-band FM (mono/stereo), narrow-band FM, AM, airband, and shortwave, with tuner-gain, sample-rate and squelch controls.

Stream anywhere

An embedded server (LiveAudioServer) puts out AAC/HLS over HTTP and HTTPS — listen on a phone, tablet, laptop or smart TV.

Favorites & scanning

Save stations, group them into categories, and run high-speed scans across a category to stop on activity.

Not just the RTL-SDR

Stream a Core Audio input, bridge Gqrx's UDP output, or speak a folder of text files through the same pipeline.

Record

Capture the live AAC stream to a file and play recordings back — or fast-download them — from the Recordings screen.

Spatial audio & filler

Per-listener azimuth / distance / reverb, plus an idle "filler" loop with periodic spoken station announcements.

The web UI, live

This is the actual front end from AntennaHead/Web/, served here as a static preview: the template tokens and server endpoints are filled by a small mock layer, so navigation, the tuner keypad, category tables and settings all work, but there is no live audio. Anything that needs a real radio shows a short "preview only" note.

Try these

  • Radio → Tuner → Wide-band FM — tap the digits, use +/− to change frequency.
  • Radio → Favorites and Categories — open a sample station or group, then try Edit and Category Settings.
  • Radio → Listen to Gqrx — the Gqrx remote-control panel: filter width, audio gain, squelch, mode, and the bookmarks list.
  • ControlBooth — the remote-control pages: pipelines, AntennaHead Radio, the AirPlay receiver, and the dsd-neo scanner.
  • Devices → Text to Speech — a sample page for speaking text through the audio pipeline, with the voice-markup guide.
  • Now Playing (top-right button) — canned status plus the spatial-audio sliders.
  • Settings — AAC bitrate, colour scheme, tap-feedback toggle.
  • Recordings and Info.

Open the demo full-screen →

Static preview · no radio connected

On Apple TV and Apple Watch

Native apps for Apple TV and iPhone & Apple Watch play the stream and control the same server. Here, AntennaHead Radio is on the air. Skip Song rings a gong, fades the song out and fades the next one in.

The AntennaHead Apple TV app's AntennaHead Radio page: On the Air, now playing Oh, Pretty Woman by Roy Orbison, with Skip Song and Stop buttons, and the sidebar of sources on the left.
Apple TV: the AntennaHead Radio page, with Skip Song and Stop.
The AntennaHead Apple Watch app's Radio page: On the Air, Oh, Pretty Woman by Roy Orbison, and a Skip Song button.
Apple Watch: More Sources › AntennaHead Radio.

Screen recordings

Short captures of the UI driving a live stream in the iOS Simulator.

AntennaHead's Wide-band FM Tuner turns your RTL-SDR into an FM radio, so you can tune in any local station and follow along with live captions. Here, dialing it to 89.1, naming it KUAR, and hearing live NPR news in Listen and Live Captions.
AntennaHead's Gqrx integration lets you listen to the popular open-source Gqrx software-defined radio receiver, and control it remotely, right from your iPhone. Here, using AntennaHead with Gqrx (with our custom Gqrx for AntennaHead app): Listen to Gqrx, control the Gqrx receiver and SDR device remotely, then tap the NOAA Morrilton bookmark (162.475 MHz) and hear the weather forecast.
AntennaHead's Audio Delay feature makes it easy to synchronize the live radio broadcast of your favorite sports announcers with the TV broadcast for the video. Here, from the Home Screen: open the AntennaHead web app, browse to Favorites, tap KUCA 91.3, hit Listen, hear the countdown fill the silent wait, then tap Delay 1 Second four times (0:19 to 0:23) and a chirp confirms the new delay.
AntennaHead's Scanner works your RTL-SDR like a modern radio scanner, stepping through a whole category of frequencies and stopping on activity so you can listen in. Here, scanning the Aviation category (Adams Field ATC) and reading real air-traffic-control chatter in Live Captions.

Using HTTPS

Plain HTTP is fine on a home network, and it's the default. If you want the connection encrypted, for example when you turn on AntennaHead's web login, turn on HTTPS in AntennaHead's Security tab. AntennaHead then also listens for HTTPS, on port 8094 unless you change it in Configuration.

In a web browser

AntennaHead can generate its own self-signed certificate (Security › Load / Generate Self-Signed Certificate). Browsers warn about a self-signed certificate the first time, and usually let you continue to the page.

In the iPhone, Apple Watch and Apple TV apps

The native apps (iPhone & Apple Watch, Apple TV) only accept a certificate the device already trusts, so the self-signed one won't work. Use a certificate from a trusted authority, such as Let's Encrypt or Tailscale, and load it as a User-Supplied Certificate (.p12) in the Security tab.

Connect by name

Enter the name on the certificate and the HTTPS port, e.g. mac.example.com:8094, not the Mac's IP address. The name has to reach the Mac wherever you listen: at home, and over your VPN if you use one. A .local name only works on your home network.

Turn it on in each app

iPhone: Use HTTPS in the server's settings. Apple Watch: it takes the iPhone's setting, or use the HTTPS switch when adding a server on the Watch. Apple TV: Use HTTPS on the connect screen. If a device doesn't trust the certificate, the apps won't connect: the Apple TV app says the certificate isn't trusted, and the iPhone app says it can't reach the server.

Build it

Requires macOS 14+, Xcode 15+, and (optionally) an RTL-SDR USB radio. Swift Package Manager resolves everything on first build.

github.com/dsward2/AntennaHead →

Latest release: v0.3.1-alpha (pre-release) — direct download (.zip, signed & notarized)