IRLP

IRLP  Information

Irlp was created by Dave Cameron who resides in Vancouver, Canada.

The aim of this project is to reliably and inexpensively link amateur radio systems without the use of RF links, leased lines, or satellites.

The IRLP uses Voice-Over-IP (VoIP) custom software and hardware.  Coupled with the power of the Internet, IRLP will link a repeater site or simplex station to the world in a simple and cost effective way. 

 Just as with any linking system, IRLP is subject to some minor audio delays which are mostly radio related. These delays are caused by the amount of time it takes for numerous radios to decode the Tone Squelch information so the first thing to remember is to slow down and be patient. (to dispel internet delay myths, the audio delay over the internet is the same as you experience when using a digital cell phone)

 IRLP operates a worldwide network of dedicated servers and nodes offering very stable worldwide voice communications between hundreds of towns and cities.  All this with unsurpassed uptimes and the full dynamic range of telephone quality audio. 

Irlp status page can be found here   STATUS .

Use Information

As with any new technology, it does take some time to adopt to operating procedures that differ from conventional FM repeater use.  This work in progress can serve as a guideline for those wishing to use their local IRLP enabled repeater node.

 COMMON MODES
There are two connection modes for an IRLP connection.  Direct one-to-one or, one-to-many via a Reflector.

Direct connect is just like it sounds where repeater (node) "A" connects direct with node "B".  With this type of link the two nodes are interconnected and no other IRLP connections are possible.  While repeaters "A" and "B" are connected, anyone attempting to connect with either node will be told by a  recording that - "The node you are calling is currently connected to callsign" however all local traffic on each repeater will be heard on the other repeater as well.

While Direct Connect is preferred for a city to city chat, the most common type of  connection in use today is via the Western Reflector (Ref 9250).  A reflector is a Linux computer that is not connected to any radio but rather sits on lots of internet bandwidth capable of allowing many repeaters to be inter-connected together by streaming the received audio back to all other connected stations.  Each reflector has 9 sub channels allowing up to 10 separate virtual reflectors to operate.   These are identified by the last digit.  For example - 9250 is the main channel with 9251, 9252 9253 etc being virtual reflectors with identical capability as the main channel.

You can always check which stations are connected to the reflectors main and sub-channels by visiting the Status Page and looking for nodes connected to individual nodes or reflectors.

REFLECTOR USE
With reflector use the first thing we must all remember is to leave a gap between transmissions.  Having said that this is a good time to list the three main rules when connected to a reflector:

Pause

Pause

Pause

Due to the slight increase in delays created by multiple Tone Squelch radios in the links between the repeater and IRLP link radio, a slight change in our normal operating procedures is required with IRLP. 

By leaving a pause between transmissions it ..... 

allows users on other nodes a chance to check in.

allows other nodes time to send touch-tone commands to drop their node.

The most important guideline to remember is leaving a pause after pressing the PTT button as well as between transmissions. 

 

ACCESSING

Most repeaters do not require the use a pre-access code to access IRLP  but if required the access code would be used in front of the node or reflector number that you are trying to contact. This information can be obtained from the node or reflector owner.   This is an example page of where to look  on the  status page under (ALL IRLP NODES )at the top of the page then click on the node number to the left and  information  is on the bottom of the page.