# SDR--
A software-defined radio application for listening, decoding, and recording. Connect radios,
channels, and displays in **Patch** view, then pin your everyday controls to **Rack** view.
Run the desktop app with a local SDR, or place the server near your antenna and connect through
a browser. Both use the same receiver engine and interface.
Read the [docs](https://sdrmm.com/docs/). Questions or ideas? Join the
[Discord](https://discord.gg/dYaRyGwBNw).
## Install
Download a desktop installer or portable server from
[GitHub Releases](https://github.com/Newspicel/sdrmm/releases), or
[build](https://sdrmm.com/docs/development/building) it yourself.
The [installation guide](https://sdrmm.com/docs/getting-started/install)
covers macOS, Windows, Linux, Homebrew, APT, DNF, Nix, and Docker.
## Start with an RTL-SDR
1. Plug in the RTL-SDR and pick it on the **Device** node. Set the rate to **2.4 MS/s**.
2. Add a **WFM** channel from **+ Node** and set it to a local FM station.
3. Wire Device `iq` to WFM `iq`, and WFM `audio` to the Speaker.
4. Start the Speaker. Press `p` on a node to pin it to the Rack.
[Your first receiver](https://sdrmm.com/docs/getting-started/first-receiver) walks
through it. [Radios](https://sdrmm.com/docs/hardware) covers other hardware.
## What it supports
- **Listening:** [AM, NFM, WFM with stereo and RDS, SSB](https://sdrmm.com/docs/user-guide/channels), digital voice
(DMR, P25, NXDN, D-STAR, FreeDV, M17), and [noise reduction](https://sdrmm.com/docs/user-guide/channels#audio-fx).
- **Decoding:** [aircraft, ships, pagers, amateur modes, weather satellites, radiosondes, DAB, DRM,
and DVB](https://sdrmm.com/docs/user-guide/decoders#catalog).
- **Displays:** [spectrum, waterfalls, maps, decoded messages, and video](https://sdrmm.com/docs/getting-started/workspace).
- **Recording:** [device IQ, channel baseband, audio, and each call](https://sdrmm.com/docs/user-guide/recording),
with a time machine and SigMF playback.
- **Finding signals:** [scanning, signal identification, band monitoring, and transmitter
hunting](https://sdrmm.com/docs/user-guide/scanning).
- **Arrays:** [coherent arrays](https://sdrmm.com/docs/user-guide/arrays),
[direction finding](https://sdrmm.com/docs/user-guide/direction-finding), and
[passive radar](https://sdrmm.com/docs/user-guide/passive-radar).
- **Location:** [GPS](https://sdrmm.com/docs/user-guide/position), [satellite tracking](https://sdrmm.com/docs/user-guide/satellites),
and a [propagation map](https://sdrmm.com/docs/user-guide/propagation).
- **Phones:** [iPhone and Android remote](https://sdrmm.com/docs/user-guide/phones) with CarPlay and Android Auto.
- **Tools:** [antenna calculator, NanoVNA, and radio programmer](https://sdrmm.com/docs/user-guide/tools).
- **Automation:** [REST, WebSocket, and MCP](https://sdrmm.com/docs/server/api), plus
[network IQ, webhooks, MQTT, and databases](https://sdrmm.com/docs/user-guide/network-iq).
## Screenshots
Spectrum and waterfall
Rack view
FT8 decoding
Signal identification
Aircraft positions
Ship positions
Slow-scan television
Amateur television
Pager messages
Broadcast FM
## Thanks
[KrakenRF](https://www.krakenrf.com), [Airspy](https://airspy.com) and
[AntSDR](https://www.microphase.cn/) provided hardware for development and testing.
Making a radio? Write to [hi@jhaag.me](mailto:hi@jhaag.me) to get it supported and tested.
## License
Copyright (C) 2026 Julian Haag.
Licensed under the [GNU Affero General Public License, version 3 or later](LICENSE).
Need a commercial license or custom work? Write to [hi@jhaag.me](mailto:hi@jhaag.me).
[Third-party notices](THIRD_PARTY_NOTICES.md) and license texts are also available in the app's
About panel.
