Linking Systems: EchoLink & IRLP
Using Repeaters
Internet linking connects repeaters across cities, states, or even countries using Voice over IP (VoIP) technology. When two repeaters are linked, a transmission on one is heard on the other — and vice versa. While more common in amateur radio, some GMRS repeaters participate in linking systems.
How linking works
A linked repeater has a computer (called a "node") connected to both the internet and the repeater's audio system. When someone transmits on the repeater, the audio is digitized, sent over the internet to the linked node, and played back through the remote repeater. The result is that two radios hundreds of miles apart can communicate as if they were on the same local repeater.
Common linking systems
- EchoLink: the most widely used linking system. Each node has a unique number. You can connect to a specific node by sending its number via DTMF tones on your radio. EchoLink also has a smartphone app and PC client, so you can listen to and talk on linked repeaters from anywhere with internet access
- IRLP (Internet Radio Linking Project): similar concept to EchoLink but uses a different protocol. Nodes are identified by four-digit numbers. You connect and disconnect using DTMF codes. IRLP does not have a smartphone app — you must use it through a radio
- AllStar Link: an open-source linking system built on the Asterisk VoIP platform. Growing in popularity due to its flexibility and open architecture
Using DTMF to connect
To connect a linked repeater to a remote node, you typically key up and send a DTMF code sequence using your radio's keypad. The exact procedure depends on the linking system and the repeater's configuration:
- Find the node number of the station you want to connect to (from online directories)
- Key up on the repeater and enter the connect code followed by the node number
- Wait for a confirmation announcement from the repeater
- Communicate normally — your audio goes to the remote repeater automatically
- When done, send the disconnect code to unlink the repeaters
Always ask before connecting. Linking ties up two (or more) repeaters simultaneously. If people are using the local repeater for a conversation, don't link it to a remote node without checking first. Some repeaters have strict rules about who can activate the link.
Linking on GMRS
Internet linking on GMRS is less common than in ham radio, but it exists. Some GMRS repeater operators have set up EchoLink or AllStar nodes on their repeaters. The FCC permits internet linking on GMRS — there's no rule against it. If a repeater listing mentions EchoLink, IRLP, or AllStar capability, the repeater owner has enabled linking and you can use it.
Limitations
- Latency: internet linking adds a small delay (typically 0.5-2 seconds) to transmissions. This can make fast back-and-forth conversations feel awkward
- Audio quality: VoIP compression reduces audio quality compared to direct radio communication. Voices may sound slightly different
- Reliability: linking depends on the internet connection at both nodes. If either node loses connectivity, the link drops
- Not all repeaters participate: the vast majority of GMRS repeaters do not have linking capability. Check the repeater listing or ask the owner