PulseScope

Open-source desktop and headless SDR scanner. Wideband receiver + multi-VFO scanner UI that orchestrates open-source decoders (rtl_433, dsd-fme, native DSP, ...) through a local HTTP/WebSocket API. Runs as a Windows desktop app, a headless Linux/Windows server, or inside Docker.

PulseScope is a clean-room reimplementation: it talks to public decoder sources through well-defined sidecar boundaries, ships its own native Rust DSP (APRS/AX.25, CTCSS, DCS, RDS, CW, DTMF), and exposes a documented HTTP/WS API. Compare its feature coverage against the category leaders in NYXSCOPE_PARITY_MATRIX.md.

Status — verified working today

• ✅ Desktop app (Windows MSI/NSIS installers, Tauri 2 webview, embedded UI)
• ✅ Headless server (--server / --api flag, optional bearer auth, rustls TLS via PULSESCOPE_TLS_CERT / PULSESCOPE_TLS_KEY)
• ✅ SDRplay RSP1B end-to-end through SoapySDR (discovery, CF32 acquisition, retune, sample-rate rebuild, teardown, reconnect)
• ✅ Native DSP decoders: CTCSS (50 EIA tones), DCS, RDS (57 kHz BPSK), CW/Morse (ITU), DTMF (16 digits), APRS/AX.25 (1200 baud AFSK with Goertzel mark/space, NRZ-I slicer, HDLC frame parser, full AX.25 UI frame parser)
• ✅ dsd-fme sidecar wired for digital voice: P25 Phase 1/2, DMR, NXDN48/96, D-STAR, YSF, M17, ProVoice (real dsd-fme.exe from lwvmobile build, runs against live RSP1B at 853 MHz)
• ✅ rtl_433 sidecar with valid u8-IQ transport and JSON parser
• ✅ Spectrum + waterfall UI, live mini-spectrum per VFO, signal-event persistence, SQLite WAL database
• ✅ IQ recording (CF32, real-verified 4M samples ≈ 32 MB)
• ✅ IQ playback (interleaved little-endian CF32 to EOF through the shared capture/scanner path)
• ✅ UDP streaming (PSAU audio + PSIQ IQ with magic/version headers)
• ✅ 79 default scan ranges from AM Broadcast through GOES HRIT/LRIT
• ✅ Docker multi-stage build + systemd unit for headless deployment
• ✅ 35 unit tests passing

See NYXSCOPE_PARITY_MATRIX.md for honest feature-by-feature classification (what's wired, what's partial, what's blocked, what's deliberately unavailable).

Quick start — server mode

# 1. build
cargo build --release --features soapysdr --manifest-path src-tauri/Cargo.toml

# 2. discover & connect RSP1B (or swap for any SoapySDR-compatible SDR)
./target/release/pulsescope.exe --server
# → bound to 127.0.0.1:8765

curl http://127.0.0.1:8765/health
# {"name":"pulsescope","status":"ok","version":"0.1.0"}

# 3. open the UI
xdg-open http://127.0.0.1:8765/        # Linux / WSL
start http://127.0.0.1:8765/           # Windows

With auth and TLS:

PULSESCOPE_AUTH_TOKEN=$(openssl rand -hex 24) \
PULSESCOPE_TLS_CERT=/etc/pulsescope/cert.pem \
PULSESCOPE_TLS_KEY=/etc/pulsescope/key.pem \
PULSESCOPE_BIND=0.0.0.0 \
./target/release/pulsescope.exe --server --port 8443
# → https://0.0.0.0:8443/  (UI + API)
# In the browser, append ?token=<your-token> once; it's cached in localStorage.

Quick start — desktop app

pnpm install
pnpm tauri dev            # hot-reload development
pnpm tauri build          # produces MSI + NSIS installers in src-tauri/target/release/bundle/

Quick start — Docker

docker build -t pulsescope .
docker run --rm -p 8765:8765 \
  -v /dev/bus/usb:/dev/bus/usb \
  --device-cgroup-rule='c 189:* rwm' \
  pulsescope

Where decoders live

PulseScope expects decoders on $PATH or in <exe-dir>/decoders/. Currently verified:

Decoder	Source / Binary	Transport	Status
rtl_433	PothosSDR 0.8.1	Sidecar, u8 IQ via stdin/stdout	WIRED, REAL-TESTED
rtl_adsb	PothosSDR	(binary available, transport TBD)	Available
dsd-fme	/c/Users/Dadud/pulsescope/decoders/dsd-fme/	Sidecar, 48 kHz mono WAV via fs	WIRED, REAL-TESTED
AIS-catcher	jvde-github v0.70	(binary available, transport TBD)	Installed, exclusive SDR

Multimon-ng, direwolf, acarsdec, nrsc5, dumpvdl2, dump978 source tarballs are checked into decoders/ (GPL redistribution permitted by upstream authors) but require a cmake + ninja/make build step on the host. The PulseScope daemon finds them on $PATH once built; until then the corresponding endpoints return explicit "decoder unavailable" responses.

Layout

pulsescope/
├─ src-tauri/                Rust backend (server + scanner core + sidecars)
│  ├─ src/
│  │  ├─ main.rs            dual-mode entry: desktop or --server
│  │  ├─ api.rs             ~150 HTTP/WS routes, auth middleware, TLS bind
│  │  ├─ scanner.rs         capture/audio workers, VFO DSP, signal detection
│  │  ├─ demod.rs           native demodulators + tone decoders
│  │  ├─ aprs.rs            native AFSK 1200 APRS/AX.25 decoder
│  │  ├─ voice_decoder.rs   dsd-fme sidecar (digital voice)
│  │  ├─ sidecar.rs         rtl_433 sidecar (ISM sensors)
│  │  ├─ depend_manager.rs  cross-platform sidecar discovery
│  │  ├─ device.rs          SoapySDR hardware lifecycle
│  │  ├─ capture.rs         bounded IQ rings + CaptureWorker + playback
│  │  ├─ audio.rs           CPAL output + UDP PSAU streamer
│  │  └─ state.rs / db.rs   shared runtime state + SQLite WAL
│  ├─ migrations/001_init.sql
│  └─ Cargo.toml
├─ ui/                       Svelte 5 + SvelteKit (hash-router SPA)
│  └─ src/routes/           19 pages: scanner, trunking, deps, recording, ...
├─ decoders/                 (git-ignored) downloaded GPL sidecar binaries
├─ docs/
│  ├─ API.md                HTTP/WS endpoint contract
│  ├─ SCHEMA.md             SQLite schema
│  ├─ PRESETS.md            scan-range preset table
│  ├─ PARSERS.md            decoder transport recipes
│  └─ BUILD.md              platform build matrix
├─ Dockerfile
├─ contrib/systemd/pulsescope.service
└─ NYXSCOPE_PARITY_MATRIX.md  honest feature coverage comparison

Configuration (env vars — server mode)

Variable	Default	Notes
PULSESCOPE_BIND	127.0.0.1	Listen addr. 0.0.0.0 for public
PULSESCOPE_PORT	8765	HTTP listen port
PULSESCOPE_AUTH_TOKEN	unset	If set, bearer token required on all /...
PULSESCOPE_TLS_CERT	unset	PEM cert bytes → enables rustls HTTPS
PULSESCOPE_TLS_KEY	unset	PEM key bytes
PULSESCOPE_API_ONLY	unset	Skip UI static mount; API-only server
PULSESCOPE_UI_DIR	auto-detect	Override static UI directory
SOAPY_SDR_ROOT	unset	PothosSDR install root for bindings
PULSESCOPE_SOAPY_UTIL	auto-detect	Path to SoapySDRUtil.exe

License

The PulseScope core is MIT (see LICENSE). Native decoders written here (APRS/AX.25, CTCSS, DCS, RDS, CW, DTMF, voice decoder scaffold) are MIT.

Sidecar decoders invoked at runtime (rtl_433, dsd-fme, ...) are GPL and remain separate processes. PulseScope communicates with them through stdin/stdout and serialised JSON / WAV — it does not link them. See docs/THIRD_PARTY_NOTICES.md for the full inventory.

Acknowledgements

PulseScope is built on the shoulders of the SDR open-source community. The decoder ecosystem is the actual hard part and is the work of dozens of upstream maintainers — see NYXSCOPE_PARITY_MATRIX.md for the upstream attribution of each protocol covered.