IRLP stand for the Internet Radio Linking Project

The website for the IRLP is IRLP dot NET

The Internet Radio Linking Project, is BC based but now global project that links amateur radio stations around the world using Voice over IP (VoIP). Each gateway consists of a dedicated computer running custom software that is connected to both a radio and the Internet. This arrangement forms what is known as an IRLP Node. Since all end users communicate using a radio as opposed to using a computer directly, IRLP has adopted the motto "Keeping the Radio in Amateur Radio".

Amateur radio (or ham) operators within radio range of a local node are able to use DTMF tone generators to initiate a node-to-node connection with any other available node in the world. Typically the nodes in IRLP have an analog FM link to one or more local repeaters so all you need to try IRLP is an analog FM radio. Each node has a unique 4 digit node number in the range of 1000-8999. A real-time searchable list of all the nodes worldwide (including their current status) is available anytime by viewing the IRLP website. There are over 3000 IRLP nodes across 7 continents.

IRLP connections are of two types: node to node, and node to reflector. Stations wishing to communicate with 3 or more nodes at the same time may accomplish this by connecting to what is called an IRLP Reflector. Reflectors are a type of conferencing system. Most reflectors on the network have 10 channels (0-9) with channel 0 being the main channel. Each reflector has a unique 4 digit node number in the range of 9000-9999. The first 3 digits consist of the reflector number, while the fourth digit represents the channel number. There are about 30 operational reflectors (including Echo Reflector 9990, which digitally records and plays back transmissions for testing purposes). Since most reflectors have 10 channels, there are approximately 300 unique reflector channels available for use.


IRLP was invented by David "Dave" Cameron, VE7LTD. Born and raised in West Vancouver, British Columbia, Canada, Cameron attended the University of British Columbia where he joined the UBC Amateur Radio Society. He built his first repeater and computer-based repeater controller in the 1990s.

Cameron installed the first three IRLP nodes in November 1997. They used the Windows operating system (OS) with VocalTec's iPhone voip phone software (not to be confused with Apple’s hardware device also called iPhone). There were problems with the software, mainly in the fact that the iPhone software was not very stable nor was it controllable. After running iPhone for close to 6 months on two additional BETA sites in Vernon, British Columbia, Canada and Saint John, New Brunswick, Canada, Cameron decided to rebuild the nodes and essentially start over. This is when the Linux OS and the Speak Freely software were first tested.

Dave Cameron designed his own interface board to interface the radio to the computer. This allowed a large amount of delay to be removed from the system because two VOX circuits were no longer being used . he also wrote my own custom control software, and modified an existing voice-over-IP software package to accommodate the project.


The final product was a combination of hardware and software that created a nearly seamless radio link between two remote sites on the internet. The product worked so well that many people can not believe that they are talking through a link at all!

On November 12, 1998, the very first VE7RHS node was installed in Gage Towers, UBC, Vancouver, British Columbia, Canada using a PC running Linux and Dave’s custom hardware and software. A few days later, the VE7RVN node came online from the residence of Michael Illingby, VE7TFD in Vernon, BC.

After this point, no further problems were experienced. So this planted the seed for the IRLP network to grow. New nodes slowly launched across Canada, followed by the United States and worldwide.

Node numbers were originally set at 3 digits in length. Due to the extensive growth of the IRLP network, an extra digit needed to be added in 2002. Existing node numbers after this change received a trailing zero. For example, if the old node number was 123, it became 1230. Most existing reflectors were also converted from single channels to 10 channels. This new type of reflector was known as a super-reflector. After all the reflectors were converted over the term "super-" was dropped for convenience.

The First 7


Location - Gage Towers, UBC, Vancouver, British Columbia, Canada

The Vancouver and Vernon nodes were tested for a few weeks before being installed. The Vancouver IRLP node was first installed on November 12th, 1998. On that day, Micheal Illingby, VE7TFD and David Cameron, VE7LTD were on top of Gage Towers fighting with our wireless LAN cards for close to 4 hours trying to get a reliable connection.

Once the connection was established, we returned home to test it from there. Things were working great, minus the audio which was unbearably loud.

Once the Vernon node was placed online a few days later, I trekked back to Gage Towers and adjusted the audio. The first IRLP connection had been made between Vancouver and Vernon.

Since that point in 1998, there have been no problems with the Vancouver node, except for the one time when Dave firewalled himself out of the node by accident.


Location - Residence of VE7TFD, Vernon, British Columbia, Canada

The machine was built in Vancouver during original testing of the system. The computer was causing problems at first, but we finally got it to respond on the net. The first tests were done using simplex on 446.000. The audio was very overbearing and seemed to have a small amount of AGC to it. We adjusted some levels, and before we knew it, we had a perfect sounding link between Vancouver and Vernon.

The only problems we have ever had with the Vernon node occurred when the wiring was attacked by something and was shorting out. This gave us intermittent connections, and was solved shortly after.


This machine will be moved and hosted by the Internet Junction in Vernon BC. That dates this history for sure, I bet many of our club members don’t remember Junction as one of the earliest dial-up ISP’s in Vernon.


Location - Rhoderick Dhu Mountain, Grand Forks, British Columbia, Canada



Location - Residence of Dave Junker VE6DJJ, Calgary AB, Canada



Location - Residence of Randy Roberts VE7AMS, Prince George BC, Canada



Location - Brunswick Square, Saint John NB, Canada



Location - University of Saskatchewan, Saskatoon SK, Canada


IRLP Today

Dave Cameron is still the primary creator and operator of IRLP globally, he now has more modern IRLP node solutions for sale like one based on the Raspberry Pi micro PC board and another still based on a PC but it’s a very small form factor rack mountable dual core system.

Clubs or Amateurs can also still build their own node from any suitable PC by just ordering Dave’s interface board for as little as $125 US.

NORAC still has one of the oldest active IRLP nodes with our 1050 node. We’ve had some challenges recently with the age of the hardware, but you may remember that Terry VE7TRZ made a valiant effort this past fall and resurrected the PC motherboard, power supply, and the hard drive to get it back online. Last time I checked it was being hosted at Brad VE7WBM’s house since the winter and snow came before the repairs had been completed.

How do I use IRLP

First find out what local repeater or gateway radio is hosting your local node. Program your handheld, mobile, or base radio for the VHF or UHF frequency just like you would for any other repeater.

Next make sure your radio is capable of DTMF tones. Those will be the keypad like buttons on the front of your handheld, or on the hand mic for your mobile. Be cautious, some base radios might work VHF or UHF, but they might not have DTMF buttons.

Next, how do I turn a link ON?

Visit the IRLP website and search for the menu item on the left side called Active Node Status and click on that menu item.

On the next page you can click on Connected Nodes and Reflector Status.

When you reach the IRLP Status Page you can start viewing the long lists of connected nodes, connected reflectors, etc. Look for a node that you want to contact, maybe located in a town or city where you have another ham friend that you wish to contact.

Once you have a 4 digit node number to test let’s get on the radio.

First off, let’s listen for a second and make sure this frequency is not in use.

Next, ID yourself and ask if the repeater is in use.

If you don’t get a reply then you should be safe to key in the 4 digit IRLP node ID in with your radios DTMF keypad. You shouldn’t send tones too fast, but also you shouldn’t need to send the tones for very long, I would hold each tone at least a second. Here’s a quick demo.

Too Fast – DEMO

Too Long – DEMO

This should be what you’re going for – DEMO

If the link works you’ll hear back an audio ID from the link node, or the node at the other end confirming your connection.

Now your free to ID over the new linked repeaters, and try to make contact with someone on the other end.

How do I unlink the repeater and exit the Node.

To connect you needed a four digit link code, but to disconnect it’s even easier with an easy to remember two digit code of 73. Yup, the universal ham radio code for best regards or often used as good bye, you just punch in 73 and you should hear that the node is unlinked. At this point it polite and protocol to ID a final time and state that the node is closed and you are clear so others may use it if they wish.


Q & A