astar¶

astar is a digital-voice client for AllStarLink and M17. It connects over the network as a softclient — no radio, no hotspot, no repeater in the path — and handles audio, push-to-talk, DTMF and level metering itself.

D-Star and System Fusion are in the macOS app too — DExtra to XLX/XRF reflectors, and YSF reflectors — with the AMBE+2 vocoder running on a USB dongle: a DVMEGA DVstick 30 or a ThumbDV / DV3000. Plug one in and both networks appear in the picker; there is nothing to configure.

Protocol, codec and audio handling live in one Rust engine; each platform gets a native front-end over it rather than a shared web shell.

Beta

astar is beta and moves quickly. AllStarLink is the primary target and takes the most testing. M17 needs nothing installed — Codec 2 is linked into the app as of 0.1.4beta. D-Star works, but only with a hardware vocoder dongle attached — see Digital voice. Other protocols are in the tree at various stages and are not claimed as working.

The download is Developer ID-signed and notarized, so it opens without a Gatekeeper override. It is Apple Silicon only — a single arm64 slice — and needs macOS 13 (Ventura) or later. On an Intel Mac, build from source. There is no Homebrew tap, no cask, and no App Store listing.

Download for macOS Build it from source

The astar popover on macOS: connected to a node, with live TX and RX meters, the levels and spectrum view, and the DTMF dialpad open

Networks¶

Network	Transport	Voice codec	Dials	Identifies as
AllStarLink	IAX2 (RFC 5456), UDP 4569	µ-law / A-law / signed-linear (8 or 16 kHz), negotiated	Node numbers	Node number, via the allstarlink.org portal
M17	UDP 17000	Codec 2 3200	Reflector + module	Callsign
D-Star (needs a dongle)	DExtra, UDP 30001	AMBE+2, on the dongle	XLX/XRF reflector + module	Callsign
System Fusion (needs a dongle)	YSF reflector protocol, UDP 42000	AMBE+2 DN, on the dongle	YSF reflector	Callsign

M17 transmits your callsign on the air; AllStarLink identifies by node number instead, and authenticates against the portal rather than a per-node secret.

D-Star voice is AMBE+2, which has no software implementation in astar: it runs on a hardware vocoder dongle, and the network appears in the client's picker only while one is attached. Digital voice covers why, and what to buy.

Where to start¶

The macOS app

A SwiftUI menu-bar client: an NSStatusItem that opens a dial popover, plus an optional Dock icon. macOS 13 or later. Build it from source.
Building astar

Toolchains, the Rust workspace, the Swift xcframeworks, and the Iced client for Windows and Linux.
astar-lib

The engine: IAX2 framing and session state, codecs, audio I/O, PTT backends, and the multi-network station facade. Pure Rust, no UI, exposed to Swift and Python through a C ABI.
Protocol notes

What was learned reverse-engineering app_rpt's IAX2 link layer and the Web Transceiver call flow, cited to source, wire captures, or RFC 5456.

Hardware¶

For push-to-talk, astar drives the generic class of USB radio interfaces — serial PTT plus USB audio. The AllScan UCI150 (WCH CH343) is the reference device, not a special case. Raw USB is the default transport and needs no driver; the tty path is opt-in and on macOS needs WCH's driver. See Hardware.

D-Star and System Fusion are hardware-only. AMBE+2 has no freely licensable software implementation, so the codec runs on a dongle — a DVMEGA DVstick 30 or a ThumbDV / DV3000, either works — Codec 2 you can install, AMBE you have to own.

Architecture¶

All protocol, audio and PTT logic lives in the Rust crates. The front-ends are views over that engine, so a feature lands once and every client gets it, with per-platform native UI.

Platform support¶

Platform	State
macOS 13+	Supported. Menu-bar app; signed, notarized `arm64` download, or build it. Intel Macs build from source.
Windows / Linux	In progress. The engine is cross-platform and an Iced client (`apps/gui`) builds and runs on both, but it is unfinished. Building it is documented; using it is not.
iOS	Targeted. The Xcode project builds a multiplatform target; there is no shipping iOS client.

The macOS app is the only published binary; everything else is built from source. Day-to-day usage documentation is macOS-only for now.

Community¶

astar on Discord — where questions get asked, bugs get reported before they are tickets, and on-air testing gets coordinated. astar is a beta client for live amateur radio networks; hearing what broke on someone else's setup is how it stops being broken on yours.

Licence¶

AGPL-3.0-only for everything in the repository, except the vendored ambe-thumbdv ThumbDV driver, which keeps its own MIT/Apache-2.0 terms. See Licence.