Tagged: plutosdr

VMA Radio Lab: DecSAT Extended into a Multi-SDR Receiver with DVB-T/T2, DAB+ and Analog PAL TV

Last week we posted about DecSAT, an open-source program by CasualArclamp that turns a HackRF One into a DVB-S/S2/S2X satellite receiver and analyzer. Now Vitor Martins Augusto has written to share his fork, 'VMA Radio Lab' (initially called DecSAT-VMA), which extends DecSAT into a general-purpose broadcast receiver and measurement tool.

The biggest difference between DecSAT and VMA Radio Lab is multi-SDR operation. VMA Radio Lab can run several SDRs at once, each with its own VFOs, including the HackRF, PlutoSDR, USRP B210, RTL-SDR, SDRplay RSP1 and Airspy. One SDR can be dedicated to a sweeping wideband overview, such as the full 950 - 2150 MHz satellite IF. It also pulls in DVB-T/T2, DAB/DAB+ and TETRA decoding from CasualArclamp's sibling projects DecDVB-T, DecDAB and DecLAB, and adds analog radio, PAL color TV with teletext, measurement tools such as a vectorscope and transport stream analyzer, and control of CrazyScan-compatible TBS tuner cards for LNB power and hardware DVB reception.

Meanwhile, the original DecSAT remains satellite-focused. Since our last post it has added support for Fobos SDR, Airspy and network IQ input (including rtl_tcp), and has merged some of VMA's early RTL-SDR, PlutoSDR, B210 and analog TV code.

VMA Radio Lab is GPLv3 and available as a Windows 64-bit build and source zip on the website. We note that TETRA audio needs a separate ACELP codec DLL that isn't included for legal licensing reasons, and the bundled development notes describe several of the newer decoders, such as AIS and ACARS, as experimental. 

Decscat-VMA Screenshot
Decscat-VMA Screenshot

AI Disclaimer: The original DecSAT lists Claude as a contributor. While VMA does not disclose it, the development notes included with the VMA Radio Lab source suggest that its extensions were also written with the help of AI.

SweepSA: A Fast Swept Spectrum Analyzer for Pluto-Style AD936x SDRs and the HackRF

Thank you to zxkmm, one of the maintainers of PortaPack Mayhem, for writing in and sharing their new program 'SweepSA', a swept spectrum analyzer for Pluto-style AD936x SDRs such as the AntSDR E310 and LibreSDR. It also supports the HackRF One and HackRF Pro, and is designed to feel more like a bench instrument than an SDR receiver app.

One of SweepSA's core features is speed. It uses the AD936x's little-used 'fastlock' feature, which stores synthesizer profiles that can be recalled almost instantly with a full LO retune. The hop, capture, FFT, and detection all run on the board's ARM CPU, so only the reduced spectrum is sent to the PC, which avoids the slow USB or network round trip on every hop. zxkmm reports sweeps of about 10 - 60 ms over a few hundred MHz, and 500 - 800 ms over the full 70 MHz to 6 GHz range. That's similar to a HackRF One, but with each segment a gapless 40 - 56 MHz wide.

Other features include four traces, eight markers, a waterfall, zero span, and CSV/PNG export. Levels are shown in dBFS with an 'UNCAL' badge until an amplitude correction file is loaded. SweepSA is free for Windows, Linux, and macOS (arm64), with downloads available on GitHub. We note that it is currently closed source, but zxkmm plans to publish the source code later.

Muxwright: A Multi-Standard Radio and TV Test Transmitter for the PlutoSDR

Thank you to Peter Holzhauser for writing in and sharing Muxwright, a multi-standard radio and TV test transmitter for the ADALM-Pluto (PlutoSDR). Peter has in the past submitted his ESPSoup, and Etherbulb projects. Muxwright is intended for home lab testing only, with the Pluto connected to the receiver under test via cable and attenuator or inside a shielded box, as radiating broadcast standards over the air requires a frequency assignment.

Muxwright can generate FM stereo with RDS/RBDS, DAB+, DVB-T, DVB-T2, DVB-C, DVB-S/S2, ATSC 1.0, ISDB-T, DTMB and analog PAL/NTSC TV, plus DVB-S2 DATV for QO-100 and other amateur bands (which of course requires an amateur radio license). The digital TV modulators run directly on the Pluto and everything is controlled from a browser dashboard. The Pluto's RX input can also be used as a monitoring receiver for expected vs. actual test reports.

The software runs on Windows 10/11 via WSL2 and is currently at Beta 0.4. The README notes that it has only been verified on the original Pluto Rev. B, and that DVB-T2, ATSC, ISDB-T and DTMB are still untested with real TV sets. The code is MIT licensed (with the FM/RDS module under GPL-3.0) and available on GitHub, however, the Windows installer is only available by request via email from the website.

Muxwright Transmitting DVB-T with a PlutoSDR
Muxwright Transmitting DVB-T with a PlutoSDR

AI Disclaimer: The project's GitHub commit history lists Claude as a co-author.

OnAir Adds Decoder Support for Almost Every Signal

Just last week we posted about OnAir, a new open-source program that started out as an easy-to-use digital and analog TV decoder for software-defined radios. It also had support for a few digital modes like ADS-B, GNSS and DMR.

In the last week, with the obvious help of Claude AI, OnAir has added experimental support for almost every single analog and digital signal and application out there. Support ranges from digital voice modes like P25 and NXDN, to HF digital modes like HFDL, to aircraft signals like ACARS and VOR/ILS, to ocean radar, to a radio astronomy integrator, to satellite decoders like Iridium and Inmarsat, to cell tower metadata decoders to Wi-Fi and many many more.

Obviously, with these decoders all being vibecoded so quickly, there is no guarantee yet that they will all work as expected. However, we did give some decoders in the program a test with an RTL-SDR. A DMR control channel was successfully decoded, and it read the calls; ADS-B showed aircraft; LTE PCI values were detected with the LTE decoder; and POCSAG messages came in cleanly.

From our own experience with Claude, Opus 5.5 is very capable of vibe-coding decoders, so there is a high chance that most, if not all, of the decoders implemented in this software will work. 

OnAir Updated to Add Almost Every Decoder Possible
OnAir Updated to Add Almost Every Decoder Possible

AI Disclaimer: This software was coded with Claude AI.

OnAir: A Digital TV and DAB Decoder for SDRs

Thank you to Kristijonas for writing in and sharing with us his project, OnAir. OnAir is an easy-to-use digital TV decoder for DVB-T2, DVB-T, ATSC 1.0, ATSC 3.0, ISDB-T, and a digital audio decoder for DAB / DAB+ and FM Radio. It also supports Analog TV modes such as PAL, SECAM, and NTSC, and data modes like ADS-B, GNSS (GPS, GLONASS, BeiDou), and DMR.

It supports various wideband SDRs, including HackRF, PlutoSDR, BladeRF, LimeSDR, USRP, Airspy R2, and SDRplay. RTL-SDRs unfortunately do not have enough bandwidth to decode digital TV channels in SDR mode, but the software still supports RTL-SDRs for narrowband signals.

The software is easy to install, with an installer .exe being available for Windows, a .deb file for Debian Linux, and a .dmg file for macOS. 

OnAir Screenshot
OnAir Screenshot

AI Disclaimer: This software lists Claude as a contributor.

Building a Homemade Weather Radar with a HackRF or PlutoSDR and Salvaged Automatic RV Dish

After nearly being hit by a tornado that NEXRAD didn't see coming, Koakno decided to build his own DIY self-contained mobile weather radar built from a $5 salvaged RV satellite dome, a HackRF or PlutoSDR, and open-source software. 

Koakno notes that NEXRAD (the US weather radar system) data is typically 4-6 minutes old, and from a radar station that is often 100+ miles away, resulting in warnings coming in too late or not being detected at all. Only professional local mobile Doppler radar trucks have the capability of detecting local tornadoes rapidly enough to take action. Koakno set out to recreate this capability on a budget.

His antenna consists of a salvaged Winegard Carryout Anser GM-5000 automatic satellite dome built for RV motor homes. The dish carries an LNB that radiates an 850 MHz signal at 10.4 GHz, which is a perfect wavelength for weather radar. The SDR hardware can either be a HackRF or PlutoSDR. As the HackRF is only half-duplex, it uses pulsed timing, whereas the full-duplex PlutoSDR uses a continuous FMCW chirp. Open-source Python software processes the results, producing a live radar display showing color-scaled reflectivity.

Importantly, Koakno addresses the licensing concerns around this project. He notes there are clauses in the amateur radio FCC legislation that support the use of automatically controlled beacons for the observation of propagation, and experimental activities in the 3cm 10.0 - 10.5 GHz amateur radio band, but he is not an attorney, so this activity may still exist in a grey area.

The screenshot below was generated via the simulation the software provides for testing the UI.

A Demo of the Weather Radar Display
A Demo of the Weather Radar Display

Testing a $100 “Fishball” Pluto+ PlutoSDR Clone

Over on YouTube, TheGmr140 has uploaded a video reviewing a Pluto+ clone SDR that he picked up for around US$100. He refers to it by its community nickname, the "Fishball", a name that appears to be used for Pluto+ clones sold specifically by HamGeek and OpenSourceSDR Lab, as distinct from other generic Pluto+ boards available on AliExpress.

Setup was straightforward: plug the OTG port into a PC, wait for it to appear as a USB drive, edit the config file to set the Ethernet IP address - no drivers required. Works immediately as a PlutoSDR in GNU Radio or GQRX. He's been running it at up to 13 MSPS and notes TX and RX coverage from 70 MHz to 6 GHz.

What is the "Fishball" and how does it differ? The tezuka firmware project (the main community alternative firmware) lists the Fishball as a distinct target from the generic Pluto+, identifying it as the HamGeek and OpenSourceSDR Lab boards specifically. It comes in Zynq7010 and Zynq7020 variants; the developer F5OEO notes a preference for the Fishball over the LibreSDR on build quality grounds.

Open-Source 0.1–3 GHz Network Analyzer using ADALM Pluto SDR

Thank you to RTL-SDR.COM reader MAKA for writing in and sharing his project with us, an open-source 0.1 - 3 GHz network analyzer using an ADALM PlutoSDR and a $15 RF bridge. The system allows you to measure S21 (insertion loss/gain) and S11 (return loss) with real-time visual feedback. MAKA writes:

Key features include:

  • FFT-based FIR filter for precise measurements
  • Simple S21 and S11 calibration workflows (LOAD & OPEN)
  • Real-time plots with smoothing and raw-data toggles
  • Interactive markers for easy dB/frequency annotations
  • Automatic export of calibration data to .xlsx for offline analysis
  • Fully open-source

The complete open-source code for the project is available on GitHub at  https://github.com/fromconcepttocircuit/pluto-network-analyzer

Over on his YouTube channel, MAKA has also uploaded a video demo and walkthrough.

RF Bridge Turns Your Pluto SDR into 0.1-3GHz Network Analyzer(Pt.1: S11/S21 Fund. & Filter Test)

Pluto Network Analyzer Pt. 2: S11 Calibration, Python Code & RF Bridge Performance