Packages Freedv

freedv

Digital voice over HF in the bandwidth of an SSB signal

• Version recorded: 1.8.11
• Categories: digital-voice
• Upstream: https://freedv.org/

What it does

Encodes speech with the Codec2 vocoder at rates from 700 bits per second upward, modulates it into an SSB-width channel, and decodes the same in reverse. Several modes trade robustness against quality; the low-rate ones are designed to stay intelligible where SSB is already unusable.

Why you would want it

It is the open digital voice mode -- no proprietary codec, no licence fee, no closed hardware, which is what separates it from DMR, D-STAR and System Fusion. The engineering claim is that below a certain signal level digital stays intelligible while analogue SSB has already turned to noise, and on a marginal path that is testable rather than theoretical.

Before it will work

A transceiver with SSB and audio in and out, PTT through hamlib or a serial line, and another station also running FreeDV -- which is the real constraint. Activity is concentrated on scheduled nets and specific frequencies rather than spread across the bands.

How it installs

• apt: freedv

Known problems

Below the threshold it does not degrade gracefully; it stops, completely, where SSB would have been merely painful. That cliff is the trade the mode makes and it surprises people used to analogue. Codec2 at 700 bits per second sounds like a robot even under perfect conditions -- this is the codec, not your audio chain, and no amount of level adjustment changes it. This is FreeDV 1.8.11, without RADE. All seven targets carry 1.8.11 (measured 2026-10-01). RADE, the neural voice mode FreeDV 2.0 introduced, is in no target's archive, and 1.8.11 has no RADE mode to talk to a station using it. FreeDV 2.x is not carried yet: its build fetches parts of itself from moving branches (docs/reference/source-build-gaps.md #9 and not-carried.md).

Keeping it current

• probe: apt policy
• strategy: apt_upgrade

Where to get help with the software itself

The FreeDV project, with David Rowe VK5DGR's Codec2 underneath. Mailing list and documentation linked from the site.

Source: catalog/packages/freedv.yaml