Imagine standing on the Dobratsch in Carinthia with your handheld radio and having a QSO with an amateur radio station in Australia — via a local VHF repeater. Sounds like science fiction? It is not. Systems like EchoLink and AllStarLink make exactly this possible by linking repeaters worldwide via the internet. In this article, we show you how both systems work, how they differ, and how you can use them.
What is EchoLink?
EchoLink was developed in 2002 by Jonathan Taylor (K1RFD) and is a VoIP-based system that connects amateur radio stations via the internet. The principle is simple: a radio amateur transmits via their handheld radio to a local repeater or EchoLink node. This node is connected to the internet and forwards the audio signal via VoIP to another EchoLink node anywhere in the world — which in turn broadcasts it over its local repeater.
EchoLink is free and available exclusively to licensed amateur radio operators. Every user must have their amateur radio licence verified before they can use the system. Over 350,000 callsigns are registered worldwide, and thousands of nodes are active at any given time.
How EchoLink works technically
EchoLink operates in three modes:
- Single-User Mode: The radio amateur uses EchoLink directly on a PC, smartphone, or in the browser (EchoLink Web at webapp.echolink.org) and speaks via microphone and speakers — without a radio.
- Sysop Mode: A computer is directly connected to a transceiver and forms an EchoLink node. Other radio amateurs can reach this node via radio and thus access the EchoLink network.
- Repeater Mode (Link): An entire repeater is connected to EchoLink. Anyone using the repeater can establish EchoLink connections.
For Sysop and Repeater mode, UDP ports 5198 and 5199 as well as TCP port 5200 are required. If port forwarding is not possible (e.g. in hotels or corporate networks), an EchoLink proxy server can be used to tunnel all traffic over a single TCP connection.
What is AllStarLink?
AllStarLink (ASL) is an open-source VoIP system for amateur radio based on the Asterisk telephony software. Unlike EchoLink, which uses a proprietary protocol, AllStarLink uses the proven IAX2 protocol (Inter-Asterisk eXchange) — the same protocol used in professional VoIP telephone systems.
The key difference from EchoLink: AllStarLink is designed from the ground up as a full-featured switching system. Nodes can be permanently connected to each other, and complex linking scenarios (hub networks, conference rooms, time-controlled connections) are easy to implement. Each AllStarLink node receives a unique node number through which it can be reached.
EchoLink vs. AllStarLink — the key differences
- Protocol: EchoLink uses a proprietary protocol; AllStarLink uses the open IAX2 protocol based on Asterisk.
- Software: EchoLink is closed-source; AllStarLink is fully open-source (GitHub: AllStarLink/ASL3).
- Flexibility: AllStarLink allows permanent node connections, macros, time scheduling, and arbitrarily complex network structures. EchoLink is simpler but less flexible.
- Audio quality: AllStarLink supports various codecs (including ADPCM, ulaw) and often offers better audio quality than EchoLink.
- Entry barrier: EchoLink is easier to set up — just install the app. AllStarLink requires a dedicated computer (often a Raspberry Pi) and some Linux experience.
- Interoperability: AllStarLink can also function as an EchoLink node via the chan_echolink driver, bridging both networks.
AllStarLink 3: The big upgrade
With AllStarLink Version 3 (ASL3), the project has made a huge leap forward. The core software has been completely modernised and now runs on Asterisk 22 LTS (Long Term Support) and the current Debian 12 (Bookworm) or Debian 13 (Trixie). This means ASL3 benefits from over 15 years of Asterisk bug fixes, security improvements, and the elimination of memory leaks that had caused instabilities in the old version.
The key innovations of ASL3 at a glance:
- Modern operating system: Debian 12/13 with current security updates instead of the outdated Debian base of the previous version.
- Asterisk 22 LTS: Long-term support, improved stability, fewer memory leaks, higher uptime.
- ASL Menu (asl-menu): A user-friendly configuration tool that greatly simplifies initial setup.
- Allmon3: A completely redesigned web interface for monitoring and controlling the node in the browser.
- Cockpit integration: Web-based system administration for the Raspberry Pi directly in the browser.
- HTTP registration: Node registration via HTTP with DNS IP resolution and fallback — more robust than the old method.
- Raspberry Pi 3, 4, 5 and Zero 2W: Official images for all current Raspberry Pi models.
- Package-based updates: Regular apt upgrades without Linux kernel updates breaking the node.
What is SVXLink?
SVXLink is an open-source voice services software for Linux, developed in 2003 by Tobias Blomberg (SM0SVX) — originally as an EchoLink client, now a full-featured repeater controller and networking system. SVXLink can control a transceiver both as an advanced repeater controller and in simplex mode, offering a modular, extensible architecture.
The key advantage of SVXLink: It combines multiple systems in one piece of software. An SVXLink node can simultaneously function as an EchoLink node, a repeater controller, and a reflector client. Modules allow flexible activation of features such as EchoLink connectivity, parrot (playback), voice mailbox, propagation reports, and DTMF control.
SVXLink Austria: FM Networking in Austria
In Austria, SVXLink Austria has established itself as a growing FM networking project, coordinated by OE8VIK (Michi). The system connects analogue FM repeaters and hotspots via a central SVXLink reflector, enabling — similar to digital voice modes — the use of talk groups (TGs).
The special feature: Unlike DMR or D-Star, SVXLink requires no digital radio. Any conventional FM handheld radio is sufficient to participate in the network via an SVXLink repeater or personal hotspot. Control is conveniently handled via DTMF tones.
The most important talk groups in the SVXLink Austria network:
- TG232 — Austria: Nationwide talk group, accessible via all connected repeaters
- TG2321 to TG2329 — Federal states: Regional talk groups (e.g., TG2328 for Carinthia, TG2329 for Vorarlberg)
- TG262 — Germany: Connection to the German FM network
- TG1232 — OE Bulletin: For distribution of the Austrian amateur radio bulletin
Currently, the following repeaters are connected to SVXLink Austria (selection):
- OE9XDV (Dornbirn): 438.3875 MHz, CTCSS 85.4 Hz, TG2329
- OE9XKV (Karren/Dornbirn): 438.625 MHz, CTCSS 85.4 Hz, TG2329
- OE9XVI (Vorderaelpele): 145.650 MHz, CTCSS 85.4 Hz, TG2329
- OE8XKQ (Gerlitzen): 439.050 MHz, CTCSS 88.5 Hz, TG2328
- OE2XHL (Kitzsteinhorn): 145.650 MHz, CTCSS 88.5 Hz, TG2322
- OE7XOT (Tarenz): 438.100 MHz, CTCSS 77 Hz, TG23271
The current repeater list and live dashboard are available at svxlinkaustria.at.
Your Own SVXLink Hotspot with the Shari SA818
If you don’t have an SVXLink repeater within range, you can set up your own access to the network with a Shari SA818 hotspot. The Shari SA818 is a compact FM transceiver with an integrated soundcard that connects directly via USB to a Raspberry Pi (model 2B or later). The transmit power is 1 watt (reducible to 0.5 W), and the device is powered via the Pi — no separate power supply needed.
The cost for a Shari SA818 is under EUR 60 (e.g., via Amazon or AliExpress). Together with a Raspberry Pi and the free SVXLink software, this creates a fully functional FM hotspot with access to the SVXLink Austria reflector, EchoLink and more. Reflector credentials can be requested at svx.oe9hamnet.at.
SVXLink — Sources and Further Links
- SVXLink Austria (OE8VIK): svxlinkaustria.at — Central information site for SVXLink in Austria with repeater list, dashboard, talk groups and configuration guides
- SVXLink Project (SM0SVX): svxlink.org — Official project site of the SVXLink software by Tobias Blomberg
- SVXLink on GitHub: github.com/sm0svx/svxlink — Source code, documentation and issue tracker
- Reflector Access: svx.oe9hamnet.at — Request credentials for the SVXLink Austria reflector
Access: Three ways into the network
1. With a handheld radio via a local repeater
The classic approach: you use your handheld radio (e.g. a Baofeng UV-5R, Yaesu FT-65, or Kenwood TH-D75) to access a local repeater connected to EchoLink or AllStarLink. You control the connection via DTMF tones — dial the node number of the target repeater and you are connected. Your contact hears you via their local repeater, as if you were in the same valley.
In Austria, there are several EchoLink-enabled repeaters. A current list of OE nodes with node numbers and short codes can be found at echolink.at. Some examples: Another valuable resource is svxlinkaustria.at by OE8VIK — the site provides comprehensive information about SVXLink in Austria, including EchoLink configuration, repeater list, dashboard and DTMF commands.
- OE1XUU-R (Vienna-Kahlenberg): EchoLink Node 6406, 438.950 MHz, short code D100
- OE3XNR-L (Neunkirchen): EchoLink node in Lower Austria
- OE5XOL-R (Upper Austria): Repeater with EchoLink connection
- OE7XOI-R (Tyrol): SVXLink-based node with EchoLink
A complete, regularly updated repeater list for Austria is provided by the OEVSV at repeater.oevsv.at.
2. With a smartphone (without a radio)
EchoLink offers apps for iOS and Android, and since late 2023 a web version (EchoLink Web at webapp.echolink.org) that runs directly in the browser — on Windows, Mac, Linux, and mobile devices. All you need is a validated callsign and an internet connection. The web version supports multiple languages, including German, and automatically detects the language setting via the browser.
This allows you to participate in EchoLink connections from anywhere in the world — in a hotel, at the airport, or in the office. Keep in mind, however, that you are speaking over the internet, not over radio. The identification requirements and general rules of amateur radio still apply.
For AllStarLink, there is no official smartphone app, but the Allmon3 web interface allows you to monitor and control your node via a mobile browser.
3. With a Raspberry Pi as your own hotspot
The most flexible solution: build your own EchoLink or AllStarLink node with a Raspberry Pi. You will need:
- A Raspberry Pi (Model 3, 4, 5, or Zero 2W)
- A microSD card (at least 16 GB)
- A USB audio interface or a ready-made radio interface (e.g. URI, DMK Engineering, RIM-Lite)
- A transceiver (e.g. an inexpensive handheld radio as a “hotspot”)
- Internet connection (WiFi or Ethernet)
For AllStarLink, download the official ASL3 image from allstarlink.org, flash it to the microSD card (e.g. with the Raspberry Pi Imager), and boot the Pi. After the first boot, the automatic setup takes about 20–30 minutes. Then configure your node using the asl-menu tool with your node number and audio interface.
For EchoLink in Sysop mode, install the software on a Linux system (e.g. with svxlink, an open-source implementation that also supports EchoLink connections) and connect it to your transceiver.
Registration and node numbers
EchoLink registration
Registration with EchoLink is free and done via echolink.org. You must provide your callsign and upload a copy of your amateur radio licence. Validation can take anywhere from a few hours to a few days. After activation, you receive a node number assigned to your callsign. EchoLink node numbers are four to six digits long.
AllStarLink registration
Registration with AllStarLink is done at allstarlink.org. You create an account, enter your callsign, and upload a copy of your licence. After verification, your first node is automatically assigned with a node number. Your node also receives a randomly generated password used during the ASL3 software setup.
You can check whether your node is successfully registered in the AllStarLink node list at stats.allstarlink.org — a green background indicates that your node is active and connected.
DTMF control: The most important codes
When using an EchoLink-enabled repeater via radio, you control connections with DTMF tones using the keypad of your handheld radio. Here are the most important commands:
EchoLink DTMF codes
- Enter node number: Simply type the 4- to 6-digit node number to establish a connection.
- D100 (in Austria): Short code for Vienna (OE1XUU-R) — available on all OE repeaters with EchoLink.
- D73: Disconnect from the last connected node.
- D74: Disconnect all active connections.
- D72: Reconnect to the last used node.
- D71: Random connection to an active node (“Random Node”).
- D78: Query status — returns “not connected” or the connected station.
- #: Disconnect (short form, configured on many nodes).
Important: The DTMF codes are generally standardised, but the exact configuration depends on the individual sysop of the node. On some nodes, the prefixes may differ.
AllStarLink DTMF codes
- *3 + node number: Connect to another AllStarLink node.
- *1 + node number: Disconnect from a node.
- *70: Query node status.
- *76: Disconnect all connections.
Here too, the sysop can individually customise the DTMF assignments. When in doubt, ask the node operator.
SVXLink DTMF Codes
- 91xxx# — Activate talk group: e.g., 91232# for TG232 (Austria), 912328# for TG2328 (Carinthia).
- 910# — Deactivate talk group: Return to the repeater’s default talk group.
- 9*# — Query active talk group: The system announces the currently selected TG via voice.
- 2# — Activate EchoLink module: Switches to EchoLink mode.
- *xxxx# — Select EchoLink node: Connect to an EchoLink node while in EchoLink mode.
- ## — Disconnect EchoLink and exit module.
- 1# — Activate parrot module: Plays back your own transmission for checking.
EchoLink and AllStarLink in Austria and Europe
In Austria, EchoLink is significantly more widespread than AllStarLink. The OEVSV actively supports the networking of repeaters via EchoLink, and the website echolink.at serves as the central resource for OE nodes. The node list published there contains all active EchoLink repeaters in Austria with their frequencies, node numbers, and short codes.
EchoLink is also widely used in other European countries. In Germany, numerous DARC local clubs operate EchoLink-enabled repeaters, and in Switzerland several HB9 repeaters are connected. AllStarLink has a smaller but growing community in Europe — particularly in the UK and Scandinavia, there are active nodes.
Particularly interesting is the option of using EchoLink conference servers. On these “Conferences,” multiple stations can meet simultaneously — comparable to a roundtable net. In Austria, for example, the OEVSV weekly bulletin is also distributed via EchoLink.
Practical tips for getting started
- Listen first: Connect in single-user mode or via the app to an active node and listen before transmitting. This gives you a feel for the procedures.
- Announce your callsign: The normal identification rules apply on EchoLink and AllStarLink too. State your callsign with every transmission.
- Mind the latency: VoIP connections have a noticeable delay (typically 0.5–2 seconds). Wait briefly after pressing the PTT button before speaking, and leave a longer pause after each transmission.
- Try EchoLink Web: At webapp.echolink.org you can use EchoLink directly in the browser — no installation, no port forwarding needed. Ideal for trying it out.
- Use short codes: On OE repeaters, short codes are often configured (e.g. D100 for Vienna). This saves time and prevents typos compared to the full node number.
- Test AllStarLink: At stats.allstarlink.org you will find the active node list. Many nodes also have an Allmon3 web interface where you can see who is currently connected.
- QSL cards: QSOs via EchoLink and AllStarLink are QSL-worthy. Note in your log that the connection was made via VoIP linking.
- For sysops: If you run your own node, ensure a stable internet connection and configure a timeout timer (TOT) to prevent the node from being blocked by continuous carriers.
Conclusion: Two systems, one goal
EchoLink and AllStarLink pursue the same goal: combining local repeater operations with the global reach of the internet. EchoLink scores with its simplicity and widespread adoption — install the app, verify your callsign, and off you go. AllStarLink offers more flexibility, better audio quality, and is future-proof as an open-source project. With the upgrade to ASL3, AllStarLink has also become significantly more user-friendly.
Whether you reach a radio amateur in Japan from the summit of a SOTA mountain in Austria via an OE repeater with your handheld radio, or participate in an EchoLink conference from your laptop in a hotel room — VoIP linking adds a fascinating dimension to amateur radio.
Give it a try — and tell us about your experiences!
73 – your oeradio.at editorial team
Transparency Notice
This article was researched and written with the assistance of AI (Claude, Anthropic). All content has been reviewed by the oeradio.at editorial team. If you notice any errors, please contact us at [email protected].
