Turn an M5Stack Tab5 and a compatible RTL-SDR receiver into a portable, touchscreen software-defined radio. OrcSDR runs its radio processing, dashboards, audio, and controls on the Tab5—no laptop, Raspberry Pi, or desktop SDR application is required after installation.
Download the latest release · Install in your browser · Installation guide · Read the User Guide · Report a bug
OrcSDR is made by Oregon Radio Company LLC, Oregon. Its home is theorc.dev, and the project has its own OrcSDR page. There's also a gear guide if you're picking out a receiver and antenna.
- Web flasher: theorc.dev/sdr/flash installs the latest release onto an M5Stack Tab5 straight from Chrome or Edge over USB (Web Serial). No tools to install. Leave Erase device unticked to preserve saved settings; selecting it wipes them. Compare the offered version with GitHub Releases, since the browser installer can lag a new release.
- Releases: stable and beta builds are on GitHub Releases.
- Nightly builds: automatic builds of
mainthat haven't been tagged yet. Flash the current nightly in your browser or view the rolling GitHub prerelease. Check the build commit before testing; nightlies are development firmware, not fully accepted releases. - Build from source: Tab5 build and flash quickstart. The standard build embeds an optional C6 update image but never automatically installs it.
- Contact: for business inquiries, email erik@theorc.dev.
OrcSDR started with a simple question: how far can the ESP32-P4 be pushed as an actual software-defined radio host? The first step was building a clean-room USB driver that let the microcontroller own an RTL-SDR as a native embedded peripheral. Once the Tab5 could sustain the IQ stream itself, that driver became the foundation for a complete radio.
The goal is not to hide a Linux computer behind a touchscreen or reproduce every part of a desktop SDR workstation. It is to build a useful, portable radio appliance: quick to start, touch-first, battery-powered, and able to listen, decode, visualize, scan, and explore signals without another computer attached.
That idea also shapes how OrcSDR is developed. The touchscreen and serial control interface exercise the same radio functions, making repeatable tests and automation part of the product rather than an afterthought. DSP changes are checked with saved captures and replay tools, while receiver controls and RF behavior are verified on physical hardware. Features are described by what actually works and, separately, how it has been validated; incomplete calibration does not turn a working dashboard into an experimental prototype.
OrcSDR is an open-source hobby project created by a radio and electronics tinkerer, with extensive AI assistance, outside review, and community testing. AI helps make ambitious work approachable, but the code still has to survive real USB hardware, real antennas, real signals, and repeatable regression tests.
Read the RTL-SDR Blog feature for more of the project's story.
- Open the OrcSDR web flasher in Chrome or Edge, connect your Tab5 by USB, and follow the page's installation instructions. Close any serial monitor using its port first. For the M5Burner alternative and its settings-reset warning, see the Getting Started guide.
- Restart the Tab5, then connect a supported RTL-SDR receiver to its USB host port.
- Connect an antenna suitable for the signals you want to receive and choose a dashboard.
Current release images include the matching ESP-Hosted C6 firmware used by the Tab5. Installation, updating, and recovery instructions are in the Getting Started guide and troubleshooting guide.
OrcSDR is receive-only. Dashboard availability and testing status vary by firmware version; see the feature status and User Guide for details.
- Home: Tune across the attached receiver’s frequency range with direct frequency entry, selectable demodulation, and live signal monitoring. Optional OrcDial control provides hands-on tuning.
- FM Radio: Listen to broadcast FM with stereo audio, RDS station information, presets, and station-seeking controls.
- AM Radio: Listen to broadcast AM with region-aware channel spacing, presets, automatic tuning, and a full-band station scan.
- Shortwave: Listen to real HF traffic with supported AM, USB and LSB modes, band-aware tuning and station memories. Maintainer-confirmed reception; coverage still depends on receiver and antenna.
- Weather: Quickly tune the standard NOAA weather-radio channels for local forecasts and weather broadcasts.
- CB Radio: Monitor the 40 Citizens Band channels with AM, USB, and LSB listening. The band-wide scanner includes a priority channel, lockouts, and an activity log.
- P25 Radio: Monitor P25 trunking control channels and follow supported clear voice traffic. Encrypted audio and Phase II voice decoding are not supported.
- ADS-B: Track aircraft from 1090 MHz Mode-S and ADS-B broadcasts, with aircraft lists, mapped positions, altitude, and flight details.
- LoRa / Mesh: Decode real unencrypted Meshtastic messages, telemetry, node details and GPS positions in passive LongFast reception. Detect encrypted frames without pretending to decrypt their contents.
- POCSAG: Receive pager transmissions and inspect decoded messages and CAPCODE identifiers.
- FT8 RX: Receive and decode FT8 amateur-radio signals, browse decode history, and hunt for activity across FT8 bands.
- ACARS / VDL2: Receive live VHF aviation datalink frames and decode supported aircraft messages, positions and flight data; unknown airline-specific formats are retained without fabricated interpretation.
- Airband: Hear live aviation arrival/departure AM voice, with 25/8.33 kHz tuning, scan/hold/skip controls, activity history and offline airport/channel data.
- Marine: Access VHF marine listening through the general receiver workspace. A dedicated marine dashboard is not yet implemented.
- Satellite: Open a general receiver workspace near 137.5 MHz for satellite-band exploration. A dedicated satellite decoder is not yet implemented.
- SSTV: Receive and decode the full supported 14-mode colour SSTV set, watch pictures build live and save images to microSD. Three modes also have documented conducted RF image/SD tests on all four primary dongles.
- Dead Air: Record real RF/audio observations and event measurements, with functioning Unit ENV III temperature, humidity and pressure inputs on Tab5. Optional VEIL-26 transforms measured values into explicitly labeled, reproducible esoteric symbols—not paranormal detections.
- RF Lab: Use the receiver as a portable RF test bench with live measurements, receiver controls, measurement sessions, and IQ recording.
- 2.4 GHz Wi-Fi: Survey nearby Wi-Fi access points, channel usage, signal strength, and advertised network security using the onboard wireless co-processor.
- Settings: Manage audio, display, Wi-Fi, storage, data packs, companion devices, and firmware information.
OrcSDR contains its own on-device signal decoding code, not just a waterfall or a remote decoder UI. The native Tab5 firmware builds distinct receive paths for:
| Family | Native decoding and processing |
|---|---|
| Broadcast | FM Radio Data System (RDS): station identifiers, RadioText and program metadata |
| Aircraft surveillance | Mode S / ADS-B frames, aircraft identity, altitude and CPR location |
| Land-mobile digital | P25 Phase I control/voice; Phase II sync and grant observation (Phase II voice not implemented) |
| IoT / mesh | LoRa chirp/packet decoding and unencrypted Meshtastic messages, telemetry, node details and GPS; encrypted-frame detection |
| Paging | POCSAG FSK/BCH and CAPCODE/message decoding |
| Amateur weak-signal | FT8; FT4 native implementation; JS8 Normal decoding backend with narrower device-validation evidence |
| Image transmission | 14 SSTV colour modes: Robot, Martin, Scottie and PD families |
| Aviation datalink | VHF ACARS MSK and VDL Mode 2 8DPSK/AVLC/ACARS, with aircraft message interpretation |
| Time reference | WWV timing-tick detection (not a full message decoder) |
The complete native decoder inventory identifies 12 protocol/mode decoding entries plus a timing detector, their actual C/C++ modules, reception evidence and limitations. HFDL and WEFAX have active development-branch implementations but are not yet working mainline RF decoders. Native AM/FM/NFM/USB/LSB demodulation, Wi-Fi scanning and Dead Air environmental/esoteric analysis are described separately so a signal-processing feature is not mislabeled as a protocol decoder.
OrcSDR running a live FM spectrum and waterfall on the M5Stack Tab5.
See Community Hardware for community-designed 3D-printable cases, keyboard enclosures, mounts, and accessories for OrcSDR.
- Axeman72's OrcSDR handheld case: featured from GitHub Discussion #202; V1 STL files and assembly notes were submitted in PR #212. The proposed Community Hardware mirror is under review pending license confirmation.
- Tab5 Keyboard Clamshell Cyberdeck: shared by Reddit user u/pixeltwisters, with STL/3MF downloads and build instructions on MakerWorld. The design is externally hosted under its own noncommercial license.
Want to share your own case or accessory? Start a Discussion. You do not need repository collaborator access to submit a build. OrcSDR maintainers review and add selected entries with credit to the original designers.
Current feature availability, status terminology, and documentation freshness audit explain what is implemented and what has narrower physical RF evidence.
Fully supported OrcSDR receivers: RTL-SDR Blog V4, V3c, V4 Lite (V4L), and Nooelec NESDR SMArt V5. All four are accepted receiver models, not experimental dongle profiles. This is a receiver-compatibility statement, not a guarantee that every dashboard, frequency, antenna configuration, or RF measurement has the same validation status. Dashboard-specific and historical acceptance limits remain documented in the feature status and project evidence.
| Receiver | OrcSDR support | Notes |
|---|---|---|
| RTL-SDR Blog V4 | Fully supported | Tested receiver with integrated V4 HF upconverter handling. |
| RTL-SDR Blog V3c | Fully supported | Tested receiver; HF below its tuner range uses direct sampling, with mode-specific control differences. |
| RTL-SDR Blog V4 Lite (V4L) | Fully supported | Tested receiver; model-specific HF routing and controls are integrated. |
| Nooelec NESDR SMArt V5 | Fully supported | Tested receiver; 40 m FT8 reception was accepted. |
| Earlier RTL-SDR Blog V3 variants | Experimental / individually verify | V3c acceptance does not automatically qualify every earlier V3 revision. |
| Nooelec NESDR SMArTee XTR / E4000 | Implemented and usable within tuner limits | The independent driver works in OrcSDR on supported frequencies. Out-of-range band dashboards may open but do not attempt invalid RF tuning. Better cross-dashboard range/availability messaging remains a UX task; this is not a driver failure. |
| Other RTL2832 receivers | Not verified | Generic USB detection is not evidence of model support. |
Antenna choice affects what can be received. Useful test reports include the receiver model, frequency and band, antenna, gain setting, OrcSDR version, observed behavior, and a serial log when available.
Maintainer-confirmed live reception and sensor operation are detailed in the field acceptance record, separately from dated laboratory and release-package checks.
| Area | Implementation |
|---|---|
| Main processor | ESP32-P4 on the M5Stack Tab5; radio control, USB, DSP, graphics, touch, and audio run locally. |
| Display and controls | 1280 × 720 touchscreen interface built with M5Unified and M5GFX. |
| Receiver connection | ESP32-P4 High-Speed USB Host connected directly to a supported RTL-SDR receiver. |
| IQ transport | Callback-only IQ delivery using three 32 KiB USB transfers, with stream and consumer-drop diagnostics. |
| Signal processing | Native on-device demodulation, spectrum and waterfall generation, RF measurements, and protocol decoders. |
| Audio | 48 kHz stereo processing and playback through the Tab5 speaker path. |
| Wireless | The onboard ESP32-C6 provides Wi-Fi over SDIO through ESP-Hosted. The C6 may run 3.0.6 or the M5 factory 2.12.6 (which keeps M5 Launcher's Wi-Fi/OTA working); a 3.0.6 image is embedded for an optional update. |
| Storage | Internal flash and NVS for firmware and settings, plus optional microSD storage for maps, data packs, logs, and IQ captures. |
| Build system | Native ESP-IDF 5.5.4 with locked component versions and repository build/install scripts. |
Antenna → RTL-SDR tuner → High-Speed USB → esp-rtl-sdr → IQ buffers
├─ DSP and decoders
├─ touchscreen UI
├─ speaker audio
└─ optional storage
The standalone esp-rtl-sdr component is a clean-room USB host driver. OrcSDR keeps receiver detection and hardware capabilities in the driver while the application owns dashboards, DSP, audio, and user workflows. The current streaming configuration is intentionally fixed at three 32 KiB transfers to preserve the tested hardware baseline.
- Native ESP32-P4 decoder inventory
- Project changelog
- User Guide
- Downloads and installation
- Offline maps: download or copy to SD (development pilot)
- Common controls and workflows
- Settings and Wi-Fi
- Troubleshooting
- Developer reference
- GitHub Wiki
Source-build requirements and commands are in the build from source guide. Advanced diagnostics and developer tools are in the developer reference. Driver contracts, porting notes, hardware measurements, and architecture decisions live in the repository's docs/ directory.
Please keep changes focused and preserve the distinction between a successful build, a successful flash, and physical radio testing. When contributing receiver behavior, document the hardware, test setup, and source of any measurements.
The current status, remaining-work roadmap, architecture and maintainer field acceptance are the current authoritative entry points. The original implementation phasing is preserved as a historical execution ledger, not a list of features still missing.
OrcSDR is under active development. The V4, V3c, V4L and Nooelec NESDR SMArt V5 are fully supported receiver models; E4000/XTR also operates within its supported frequency range, with invalid out-of-range tune requests intentionally suppressed. Remaining work includes better cross-dashboard compatibility messaging, additional RF characterization and selected digital-protocol interpretations.
OrcSDR is licensed under GNU AGPL-3.0-only, with separate commercial licensing available as described in LICENSING.md.
Hardware: M5Stack Tab5 · Receiver driver: esp-rtl-sdr · Guide: OrcSDR User Guide
OrcSDR is made by Oregon Radio Company LLC · theorc.dev · erik@theorc.dev
If this project is useful to you, consider supporting its development. Across ORC projects, support helps fund development time, hardware testing, receiver compatibility, and decoder work.