Search results

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.

FreeDV plus Video adds simultaneous digital voice (FreeDV) to ZL2AFP's OFDM TV (see OFDM TV page listed under Software/SSTV and FreeDV page listed under Software/Digital Voice). An older version of OFDM TV is used, modified for compatibility with FreeDV. The video is 1 frame/sec, 36-lines, with full color. Total bandwidth is 3.5 kHz.

The SM1000 allows you to run FreeDV without a PC. Connect the SM1000 to your SSB radio, and you now have Digital Voice (DV). You don’t have to buy a new radio to run Digital Voice! It’s based on a STM32F4 micro-controller, has a built in microphone, speaker amplifier, speaker, and transformer isolated interfaces to your radio.

SmallDV is an embedded FreeDV for Raspberry Pi from Matt KK5JY

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.

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).

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.