# Release Notes — v0.6.0-pre

## Hardware-ready milestone

The system is now ready for first real hardware TX tests with ADALM-Pluto (PlutoSDR).

### Build for PlutoSDR
```powershell
go build -tags soapy ./cmd/fmrtx
.\fmrtx.exe --list-devices
.\fmrtx.exe --tx --config docs/config.plutosdr.json
```

### What's proven
- 82 tests pass (DSP, spectral, operator truth, engine)
- FM IQ magnitude verified: all samples |I²+Q²| = 1.000000
- Spectral verification: 19 kHz pilot, 38 kHz stereo, 57 kHz RDS confirmed
- Continuous TX engine runs stable for >60s in tests
- IQ resampling 228k→528k preserves signal magnitude

### First smoke test procedure
1. Connect PlutoSDR via USB
2. `.\fmrtx.exe --list-devices` — verify device shows up
3. `.\fmrtx.exe --tx --config docs/config.plutosdr.json` — start in idle mode
4. `curl -X POST http://localhost:8088/tx/start` — begin transmitting
5. Tune FM receiver to 100.0 MHz — should hear 1kHz/1.6kHz test tones
6. `curl http://localhost:8088/runtime` — check telemetry
7. `curl -X POST http://localhost:8088/tx/stop` — stop
8. Ctrl+C to exit

### Safety defaults
- TX is OFF by default — requires explicit start
- outputDrive 0.3 in PlutoSDR config (conservative)
- Limiter enabled with ceiling 1.0
- Pre-emphasis 50µs (European standard)