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The FreeDV project offers a suite of digital voice modes for HF radio, with its flagship mode being the Radio Autoencoder (RADE). This free GUI application for Windows, Linux, and macOS allows any SSB radio to be used for high-quality digital voice communications. The technology, including the Codec 2 speech codec, is 100% open source under the GNU Lesser Public License v2.1 and two-clause BSD license, fostering experimentation and innovation in amateur radio digital voice. Development is managed by a six-person Project Leadership Team and funded by an ARDC grant, with Software Freedom Conservancy as the financial sponsor. Controlled testing indicates that RADE technology performs comparably to SSB on both high and low SNR channels. The resource lists various FreeDV nets and activities, including a worldwide activity day, and specific nets in Argentina (7.045 MHz LSB), Australia (7.197 MHz LSB), the UK (3.640 MHz LSB, 5.3685 MHz USB), and the USA (7.181.5 MHz LSB, 7.177 MHz LSB). Support resources include a mailing list, Discord channels, and a Zoom channel. Documentation such as the FreeDV GUI User Manual and the SM1000 Manual are provided, alongside access to source code for RADE, FreeDV GUI, and Codec 2.

Boasting an FM demodulation rate of **1,235 Msps** and a DMR speed of **369x realtime**, SDR-- is a software-defined radio application designed for patching together radio components across macOS, Windows, and Linux platforms. It facilitates connecting a receiver to various channels, which then feed into speakers, maps, or recorders. The software supports a wide array of audio modes including AM, NFM, SSB, CW, FM stereo, RDS, DMR, FreeDV, D-STAR, Fusion, NXDNP, P25, and dPMR, alongside decoding numerous events and messages such as ADS-B, ACARS, VDL2, HFDLA, AIS, NAVTEX, DSC, POCSAG, FLEX, ERMES, FT8, FT4, WSPR, APRS, RTTY, PSK, ISM sensors, and time signals. Beyond audio and data, SDR-- also handles video modes like SSTV, ATVDVB-S, and DVB-S2. It provides comprehensive displays including spectrum, waterfall, constellation, and map views, all integrated with decoded messages. Advanced features include scanning, signal identification, satellite tracking, direction finding, and passive radar capabilities. The application offers remote control options via REST, WebSocket, MCP, and event forwarding, allowing integration with external tools. It can operate on a desktop computer or be deployed on a server, such as a _Raspberry Pi_, for remote access, providing flexibility for shack setups or antenna-side installations.

SmallDV is an embedded FreeDV for Raspberry Pi from Matt KK5JY

The Quantum Spectrum DSP M2, launched in June 2023, provides a 192/138 KHz band view and _Slip-tune_ independent tuning, enhancing existing radios with advanced Digital Signal Processing via an affordable touch display. It integrates with various radios, offering a significant upgrade to their operational capabilities and user interface. Building on this, the M4 Spectrum DSP, introduced in January 2025, incorporates transceiver functionality with 0.1-20 watts TX power, effectively converting any radio into a next-generation system. Both models utilize a powerful 1027 DMIPS processor, significantly outperforming common microcontrollers like the Atmega 328. The M4 further includes a 5-inch day-bright XGA touch screen, AI capabilities, IF/RF input, and a wide-band radio receiver option. Quantum SDR also offers the _Quantum Spectrum-G90_, a dedicated integration for the Xiegu G90, which replaces the stock 1.8-inch LCD with an upgraded touch screen interface. This integration adds extra modes such as FM and _freeDV_, connecting via the Xiegu's IQ and Comm ports to provide a fully enhanced operating experience at a competitive price point.

Demonstrates ZeusSDR, a WebGL-native station console for _OpenHPSDR_ radios, including Hermes-Lite 2 and ANAN-class transceivers. The software integrates a 2D and 3D WebGL/WebGPU panadapter with click-to-tune functionality, alongside native FT8/FT4 and FreeDV digital voice modes, eliminating the need for external software like WSJT-X or virtual audio cables. It features a protected transmit chain with SWR-trip and TX-timeout, and supports _PureSignal_ linearization on Protocol 2 for enhanced signal quality. The console incorporates a broadcast TX chain with a noise gate, 10-band EQ, compressor, exciter, bass, reverb, and VST3/Audio Unit hosting for advanced audio processing. A comprehensive logbook is included, offering contact history, a 3D NASA globe, DX radar, and analytics for DXCC/WAS/grids, with ADIF and LoTW integration. Amplifier panels for RF2K-S, KPA500, and SPE Taurus are also provided. ZeusSDR supports both OpenHPSDR protocols (P1 + P2) and utilizes WDSP from Thetis. It is available for Windows, macOS, and Linux, with a public listening feature allowing others to view live waterfalls and use virtual receivers with Zeus DSP, including NR, NB, ANF, AGC, and filters. The software is open-engine, following the PowerSDR–OpenHPSDR–Thetis lineage.

FreeDV uses an audio codec as a software based modem to decode and encode the voice and text data from your computer. The data is encoded and then is transmitted over the HF radio using AF signals that can then in turn be decoded by the receiving station.

Don Trynor, VA3XFT, created EvoHam to provide guides, reviews, and tools to help ham radio operators navigate the world of digital voice modes like DMR, D-STAR, Yaesu Fusion, P25, NXDN, M17, and FreeDV. The website aims to make this technology more accessible and enjoyable for beginners, intermediates, and experienced hams alike by offering clear and approachable information. With years of experience in the field, EvoHam is a modern hub for all things related to digital voice in the amateur radio community.

RadioLog is a free amateur radio logbook software for Windows 10/11 (x64) that integrates QSO logging with real-time DX Cluster spots and _RigControl_ capabilities. It supports ADIF, eQSL, and LoTW for logging and export, along with specific modules for contest operation, including automatic scoring and _Cabrillo_/EDI export for HF and VHF contests. The software also features a dedicated portable mode for SOTA, POTA, WWFF, and CB/11m activations, offering a distinct logbook for these activities. The application includes an integrated _RTL-SDR_ auxiliary monitor for visual and audio support during operation, and offers three CAT connection methods: direct RadioLog control, Hamlib managed by RadioLog, or an external rigctld server. Recent updates, such as those in v4.0.2, focus on interface polish, consistent dark theme application, and layout bug fixes, including VFO frequency display with thousands separators. The software also provides reciprocal synchronization with QRZ.com Logbook, allowing both upload and download of QSOs, and supports various digital voice modes like DMR, C4FM, D-STAR, FreeDV, and M17.

The Pikes Peak Radio Amateur Association (PPRAA) serves as an ARRL Special Service Club, providing a calendar of events and activities for its members and the wider amateur radio community. The resource details upcoming events such as the USS Pueblo Memorial Museum Ships Weekend activations, a Cubical Quad Antenna Workshop, LARCFest, and various hamfests including Dayton Hamvention and Duke City Hamfest. It also lists on-air activities like a FreeDV digital voice mode event on 10 meters, a Black Friday Simplex Event on 2M and 70cm, and a 10m event for Technician class operators, emphasizing SSB privileges from 28.300 to 28.500 MHz. The PPRAA's event schedule includes educational opportunities like a Technician Class and a Soldering Workshop, alongside social gatherings such as the PPRAA Picnic and Car Show. Past event summaries highlight successful activities like the 2024 Megafest Raffle, Winter Field Day, and multiple fox hunts utilizing frequencies like 147.420, 147.480, and 147.540 MHz. The club actively supports POTA activations, exemplified by their AF0S park activation at Cheyenne Mountain State Park, and participates in historical commemorations like the USS Pueblo Memorial operations, demonstrating a broad engagement across various amateur radio facets.

For amateur radio operators seeking to engage in digital voice communications, DVNets provides a centralized, community-verified directory of active nets. It organizes net schedules by **digital mode**, day, region, and access details, covering systems such as DMR, BrandMeister, D-STAR, System Fusion (YSF/C4FM), AllStar, EchoLink, M17, P25, NXDN, Wires-X, IRLP, and FreeDV. The platform offers specific connection information including talkgroups, reflectors, and rooms to facilitate participation in these digital voice activities. DVNets currently lists 374 active nets across 10 digital modes and 11 countries, with 70 community verifications ensuring accuracy. Users can browse nets by specific digital voice mode, view a weekly schedule, or explore listings by region, including the United States (142 nets), Canada (38 nets), and the United Kingdom (27 nets). The directory also features a "Happening soon" section, displaying nets active or starting shortly in the user's local timezone.

Demonstrates _FreeDV RADE_, an open-source digital voice mode for HF, which combines machine learning with classical Digital Signal Processing (DSP) to achieve improved speech quality and spectral efficiency. Released in June 2025 by ARDC grantee FreeDV, RADE operates at Signal-to-Noise Ratios (SNRs) as low as -2 dB and occupies approximately 1.5 kHz of bandwidth, half that of a typical SSB signal, while transmitting about 8 kHz of voice audio. The mode also features an optimized Peak-to-Average Power Ratio (PAPR) for efficient power amplifier use, reducing heat and consumption. Users, such as _VK3TPM_, report significantly improved listening ease compared to analog modes, particularly in high HF noise environments, making it easier to conduct nets across various Australian states. The mode's integration into popular radios like the _FlexRadio 6000_ series allows direct operation without external computers. A C library for RADE is available, facilitating broader integration into other radios and SDR programs, with development continuing on FreeDV RADE v2 to further narrow bandwidth below 1 kHz.

The Llanelli Amateur Radio Society (LARS) website details the club's offerings for both licensed operators and those new to amateur radio, including shortwave listeners and individuals pursuing Foundation, Intermediate, or Full licenses. It highlights opportunities to learn radio techniques, explore digital modes such as C4FM, D-Star, DMR, and FreeDV, and participate in contests and social events. The club aims to foster a supportive environment for experimentation and knowledge sharing among its members. Member testimonials illustrate practical applications, such as a new licensee making a 1000km contact via a repeater after being inspired by space exploration, and another quickly passing the RSGB Foundation exam. The site also features accounts of members progressing to Intermediate and Full licenses, with one Full license holder continuing to learn new modes like CW and digital, and engaging in activities like Parks on the Air (POTA).