 |
|
|
|
|
British Columbia Frequency Modulation Communications Association
IRLP - Internet Radio Linking Project
Thanks to Dave Cameron, VE7LTD, Amateur Radio is receiving a new breath of life through his Internet Radio Linking Project. Many repeaters around the world that were being under-utilized are now alive and well with radio amateurs now speaking with other hams around the world.
IRLP uses Voice-Over-IP software and a custom interface board to interface your VHF or UHF amateur radio to repeaters around the world via the internet. You must use a radio to access IRLP -- you cannot connect directly from the internet or without an amateur radio license.
More information on IRLP itself can be found at www.irlp.net.
We encourage the use of this new method of global repeater linking system, but operating on IRLP differs slightly from conventional repeater use, so before you key up please read through our user guidelines.
IRLP on VE7RPT
The BCFMCA has installed the IRLP interface and connected it to our system via the RLC-3 repeater controller. This gives us the most flexibility, and allows us to connect it to any of the available analog repeaters on the mountain.
Under normal circumstances, VE7RPT-VHF and VE7RPT-UHF are linked together. In turn, they are both linked to the IRLP node. This allows anyone on either VHF or UHF to use IRLP at the same time.
The repeater system will accept all incoming IRLP connections from around the world. You will hear a voice announcement when a connection is established.
However, in order to connect VE7RPT to other nodes you must be a BCFMCA member. Like the autopatch, there is a prefix required in order to "dial-out" and connect to other IRLP nodes.
Like the autopatch codes, please don't discuss IRLP access codes over the air. We have already experienced both licensed and non-licensed people with radios trying to access IRLP on our repeater. There are bootleggers and lids no matter where you live, and discussing codes off the air is a good policy for both autopatches and IRLP. Its your repeater system that you support.
That being said, please assist anyone that is having trouble connecting to another node. Please also jump in and help guests if they wish to try out IRLP and connect to another node... but you bring up the node and drop it at the end of the QSO.
IRLP Connections
There are two different types of IRLP connections possible:
Direct Connect or "Point-to-Point"
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.
"One-to-Many" Via Reflector
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.
Reflectors start with a "9" in their node address. Each reflector also 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.
Currently active nodes, their connections, and reflector status is available from www.irlp.net/status.html.
Our IRLP Node is currently connected to: 9009 .
IRLP Commands
Using IRLP is very straight forward. There are only two commands you need to remember (they're also listed in your roster).
To connect to another node dial XXXYYYY. Where XXX is the IRLP prefix assigned by the BCFMCA, and YYYY is the remote node you want to connect to.
All IRLP nodes and reflectors are 4 digits long.
To disconnect after your QSO, dial XXX73. Where XXX is the same IRLP prefix as used above, and 73 is the hang up code.
Making a Direct Connection
First of all listen on the local repeater for at least 15-30 seconds before transmitting, and then ask if the repeater is currently in use. Assuming all is clear, identify yourself and give the node name or number you wish to call.
Example: "VE7xxx for the Sydney node" - - then enter the ON code (prefix+node number) for the node and release your PTT.
The local repeater should come up with a carrier as it waits for the connection to be authenticated. This can take a few seconds of dead-air so don't be concerned. When the connection is confirmed, the voice ID of the destination node will be transmitted back to you as well as your nodes voice ID to the other repeater.
NOTE: If your node is already connected to another node or reflector, a greeting will play saying, "Your node is currently connected to...ID of the connection"). In this case, confirm if anyone desires the connection to remain up before dropping by using the OFF code (prefix+73).
Once connected, and after hearing the confirming voice ID, wait at least 15 seconds before transmitting as:
- The repeater may be in use, and your entry may have occurred between transmissions.
- The voice ID of your node is longer than the voice ID of their node, and the connection is not made until the ID is fully played.
- Their computer may be slower, and hence take longer to process the connection than yours.
Press and hold the microphone PTT for a second and then announce your presence and your intention such as you are calling someone specifically or just looking for a QSO with another ham in that city.
If no response is heard, announce your call and your intent to drop the link, and then dial OFF code. Not only is this courteous, it is a regulatory issue in some countries you may be connected to.
Some nodes are configured so you cannot connect to them if that repeater is active. In this case you will receive the message "The node you are calling is being used locally". If you receive this message wait 5 or 10 minutes and then try again.
If you stay connected to a node and there is no activity on your repeater for 10 minutes, the connection will time out and automatically disconnect with a voice ID disconnect message on both nodes.
Connecting to a Reflector
As above, listen to your local machine for local use, and then announce your intention for the Reflector before dialing the ON command.
When you hear the confirmation ID, always WAIT at least 15 seconds before transmitting, as you are most likely now connected with many repeaters and a QSO could be in progress.
If after 15 seconds you hear nothing, identify yourself and indicate you are listening to the Reflector from "Vancouver, BC, Canada". With the world wide IRLP activity your local repeater now has world wide coverage, thus the suggestion to better detail your QTH.
Don't be in a hurry to hear someone come back to you. You may have to do a bit of pleading from time-to-time to un-lodge someone from whatever they are currently involved with.
By default, connections to the reflectors now time out with no activity, however many node owners set this period for a long period so it is not unusual for repeaters with minimal traffic to stay connected to the Reflector for extended periods of time. When or if the node times out from a Reflector connection, a standard time-out greeting will precede the timeout saying, "Activity time out ... Reflector xxxx, link off".
If you hear or wish to engage in a prolonged rag-chew on your local repeater (long discussion of a local nature), out of courtesy to other node listeners, drop the reflector.
Talking on IRLP
Using IRLP is slightly different than normal repeater conversations. You must remember to be patient and take some extra time during your QSO. It is important to remember when you key up, wait 1-2 seconds before you start to talk. There are delays in getting the path set up over the internet, and if you don't wait, the first part of your sentence will be missed.
Some good practice tips:
- DO pause between transmissions to allow for control codes and to let others in.
- DO hold your microphone PTT for about 2 seconds before talking to allow all systems time to rise.
- DO NOT rag-chew on your local repeater while connected to a Reflector.
- DO pause for 15 seconds after connecting to a Reflector to see if other stations are already talking.
- DO identify before sending DTMF command tones (and make sure your signal is good enough that you can reliably bring down any connection that you initiate).
- DO NOT discuss up/down codes on the air -- please refer people who want information to a control op or www.bcfmca.bc.ca
- Remember: anything you do on an IRLP reflector can be heard on the participating linked repeaters around the world.
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:
- 1. Pause
- 2. Pause
- 3. 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.
Reflector Round Tables
Round tables are conversations involving more than 2 parties. Unlike a net, a roundtable requires some organization to keep the conversation thread passing in an orderly fashion from party to party. Do not become intimidated if a group grows and, if mobile, do not be overly concerned if you are unable to remember all or any callsigns. Just try and remember the call and or name of the next station that you pass it to.
If you are listening and wish to break into a conversation, let a cycle go by so you know the participating station are, then announce your callsign during one of the "pauses". You should be recognized and then when finished with your transmission be sure to specify who you are turning it over to. If you do not specify a station to pick up the connection chaos will result as 2 or more stations may try to talk at once.
Announcing Your Presence
Announcing you are looking for a QSO, or acknowledging someone else's call differs from your local repeater were you usually just give your call. With IRLP, your transmission is now being heard on many repeaters around the world, and others may not just be sure what your intentions may be.
To resolve this, it is a good idea to give your callsign (phonetically) along with your name and your QTH and state you are monitoring for a call. Many listeners are mobile and may only pick out your prefix, your name or possibly just your QTH.
Establishing a Contact
When you hear a station that you wish to speak with, always identify who your call is meant for. It is not a good idea to simply state your call, but rather your call and your intentions.
Scenario: Several stations, including a DX station, complete a QSO and you wish to contact the DX station.
Action: VK3xxx this is Joe VE7xxx in Vancouver, BC.
By doing this rather than just IDing with your call, you leave no question who you wish to speak with. A simple ID many times goes unanswered as neither station knows who you are calling.
Breaking into a QSO
When an existing conversation is underway and the topic of conversation is of interest, just give your callsign between breaks and the next station to take it should acknowledge you and bring you into the QSO.
PLEASE do not break into an existing QSO because you want to work one of them. This is poor ham radio etiquette and on HF would result in a severe chastisement :-)
Finally, if you still have any questions, please contact us.