Heads up: this is still very early. sdrtop is in early development and proud of it. Things will move, numbers will get sharper, and some pixels are still cooking. If something looks broken, it's either a bug or an undocumented feature - flip a coin, then open an issue. ❤️
This is the first tagged release of sdrtop, and it's a chunky one. Roughly 70 commits since the experimental RTL-SDR rollout went into turning it from "a spectrum with some diagnostics" into something that actually feels like an instrument. Two presets carry this release.
🛰️ The Command Rail - the new default cockpit (1)
The view sdrtop now opens on. A slim header plus a left instrument rail built for reading at a glance:
- a big segmented frequency hero (block-font VFO readout)
- an analog S-meter
- the HUNT · MONITOR · BENCH mode tabs, whose lead card follows what you're doing
- recall slots with live activity pips - park a frequency, jump straight back to it
- a SIGNAL zone where SNR · PWR · NF · SAT each ride their own little braille oscilloscope trace right beside the value
- the gain chain and stream health round it out, with the bonded spectrum + waterfall filling the rest
Press c to drive it, ←/→ to tune. All dials, no autopilot. It's a radio, not a self-driving car.
🔬 Lab IQ Diagnostics - rebuilt from the ground up (5)
The IQ preset got a full redraw into a proper bench instrument:
- analog null-meters for DC offset, amplitude/phase imbalance and image rejection ratio (IRR) - centre is ideal, the needle shows the deviation
- a persistence constellation: a phosphor-style I/Q cloud coloured by density, with reference grids and a fitted covariance ellipse whose stretch reads amplitude imbalance and whose tilt reads phase imbalance
- an IQ histogram with a Low/Mid/Clip breakdown and PAPR (crest factor) that fingerprints the signal type at a glance
- a dense fallback layout so it stays readable when the panel gets squeezed into a tiny split
Also in this release
- Bonded spectrum + waterfall sharing one frequency ruler, redrawn in high-res braille with a height-based colour gradient and sharper peak detection
- Lab instrument mode with banner + marker panels, plus sweep and signal panels that can log a target snapshot
- Cycle the look on the fly: waterfall palettes and spectrum styles
- RTL-SDR ARM build fix (thanks @gorkemgun 🙌) - USB string buffers now build cleanly on ARM
- A reorganised README + docs: a collapsible gallery and the new cockpit documented end to end
Where this is going
The Command Rail and Lab IQ are the two presets that are genuinely there. The rest - the RF chain, timing, histogram, sweep, and the micro field views - will steadily fall in line with the same look and the same rigor. The plan from here is more derived measurements, broader calculations, and refined math so the numbers are not just present but trustworthy. Every lab panel already stamps itself [STALE] the moment RX stops, because the only thing worse than no data is confidently wrong data.
Get it
Linux · HackRF One or RTL-SDR. Grab the Source code (zip) below and build it:
cargo build --release
./target/release/sdrtop
Full requirements and instructions in the README.
73 de sdrtop. 📻