Walnut Ridge Amateur Radio Club

Walnut Ridge Amateur Radio Club ~ KE6WUK

Morse

I.R.L.P. Internet Radio Link Project

Introduction

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IRLP stands for the Internet Radio Linking Project. The aim of this project is to link radio systems separated by long distance without the use of expensive leased lines, satellites, microwaves, or controllers. A simple and easy system to link radio systems together using the Internet as the communications backbone.

The IRLP uses Voice-Over-IP (Speak-Freely) software and the power of the Internet to link radio systems across the world. The IRLP system uses its own custom interface board and software suite which makes interfacing radio systems to the world simple and cost effective.

Goal

It is not the goal of this project to compete, but to work along with other networks to improve the technology and improve radio linking communications for all involved parties. The people who benefit most from the IRLP are its users.

History of IRLP?

The Internet Radio Linking Project was started back in November of 1997 as an attempt to use the internet to link radio systems across Canada. The first full time link that was established ran from Vancouver, B.C. to Saint John, NB using VocalTec's Iphone. The link had many problems and was shut down in March of 1998 due to the numerous computer crashes and repeater lockups it was causing, and the lack of user control over the system.

David Cameron, VE7LTD set out to design a better way to use the same technology to perform the same task, while improving usability, user control, and sound quality. David's first breakthrough was to replace the existing operating system, Windows, with a more stable and versatile operating system. David chose, Linux, an open source form of the operating system UNIX designed by Linus Tovolds, because of its superior networking characteristics, its reliability, and its ease of programming.

David 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. David also wrote his 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 works so well that many people can not believe that they are talking through a link at all.

For more information about the history of Ham Radio and Voice-over-IP

Modes of Operation

There are two modes of IRLP operation

Reflector Mode - Streaming Multiple Audio Streaming
- Much like a party line - everyone hears everyone else
Point to Point Mode - Only two repeaters are linked
- This mode is much like linking two repeaters together via a link radio or remote-base

IRLP Operation

IRLP is very much similar to other linked repeater systems. The only difference is that the link is done via the Internet utilizing VoIP (Voice over IP) vs.. a telephone pair or a RF link via radio or microwave.
What this means is that when you push your Push To Talk (PTT) button you are actually keying ALL repeaters in the network PTT as well.
- (This could be only one Repeater System in a Point to Point Connection or many repeater Systems virtually all over the world in the Reflector Mode)
You quite literally have worldwide access to other IRLP nodes around the world that you can link to via DTMF command

Using the IRLP

There are some courtesy's and protocols that you must follow:

As mentioned before, you are keying up one to many transmitters around the world. This takes TIME!! Before you speak, press your PTT Button and pause for 2-3 seconds to allow all the systems to key-up.
When a person comes back to you WAIT for 3-4 seconds before responding... this allows others to join in the QSO and more importantly, allows node control operators to disconnect from the IRLP Network. Only one node can "talk" at a time and that includes controlling!!
*** REMEMBER*** Like other Amateur Radio modes it is a GLOBAL medium and your actions are a reflection of you, the node owner, hams in your area and the citizens of the country you are from!!

For More Information

KE6WUK List Server, at Yahoo Groups:
- http://groups.yahoo.com/group/ke6wuk_repeater/
For IRLP Operating Guidelines, on the WWW see:
- http://www.irlp.net/03-background/guide.html
For General Information about IRLP, on the WWW see:
- http://www.irlp.net
For Node Activity and connection Status, on the WWW see:
- http://status.irlp.net/
For IRLP Node Map Page, on the WWW see:
- http://www.ipass.net/~jimprice/irlp/

*Resources: www.irlp.net & Jon Andrews K1IMD