What is IRLP IRLP Internet Radio Link Project

What is IRLP? • IRLP (Internet Radio Link Project) is a method to interconnect different two-way FM radio transceivers together worldwide using the Internet as the backbone.

What is an IRLP Node? • An IRLP Node is a radio receiver and transmitter, which is interfaced to a PC running IRLP “Node" software connected to the Internet.

Common Node Types

IRLP Nodes and Reflectors in North America

IRLP European Nodes

What is an IRLP Reflector? • A reflector is a PC on the Internet running IRLP "Reflector" software. • The reflector has no radios connected to it. It allows multiple individual IRLP nodes to simultaneously connect to it, so all the individual IRLP nodes are now tied together, forming a single multiuser conference connection.

9000 REF 9000 Vancouver BC Canada 9070 REF 9070 Alaska Reflector AK USA 9100 REF 9100 Toronto Reflector ON Canada 9200 REF 9200 Indianapolis IN USA 9210 REF 9210 Raleigh NC USA 9250 REF 9250 Western Reflector NV USA 9300 REF 9300 Saskatoon Reflector SK Canada 9310 REF 9310 Fredericton NB Canada 9350 REF 9350 LAX - [WALA] Hub CA USA 9400 REF 9400 Quebec City - GSM Only QC Canada 9450 REF 9450 Dallas TX USA 9500 REF 9500 Sydney - Virtual PUB NSW Australia 9600 REF 9600 Philadelphia PA USA 9610 REF 9610 St. John's - GSM Only NL Canada 9700 REF 9700 Lancaster LANCS England 9730 REF 9730 Indiana Regional IN USA 9800 REF 9800 Scandinavian Reflector Angered Sweden

How Does IRLP Work? • The microphone and speaker audio, and the PTT and COS lines from a transceiver, are connected to a PC sound card and IRLP interface card. • The IRLP software makes the Internet connection between two IRLP nodes or one IRLP node and a reflector. • The receive and transmit audio is sent via Vo. IP (Voice over IP) data streams.

How it Works… • When IRLP nodes are connected, audio from the sending node is transmitted on the receiving IRLP node, pending a small Internet propagation delay at the receiving node. • When your IRLP node is connected to a reflector, when you transmit, your voice is transmitted on all IRLP nodes connected to the reflector.

Anything Unique About Using IRLP? You will need to wait ~2 seconds before talking after pressing your microphone’s PTT (Push-To-Talk) button. This will give time for the Internet links to sync up and prevent the first word or two of your transmission from being chopped off. When the other station finishes talking, wait until after you hear the courtesy beep before you press your PTT. The repeater IDs every 10 minutes and if you “Quick Key” your PTT, the ID will over-ride your transmission. Also by not “quick keying, ” you allow other stations a chance to break-in. Occasionally internet packets are lost or arrive late. These cause dropouts or breaks in the received transmission.

How Does IRLP Work ? • IRLP uses Voice-Over-IP (Vo. IP) software called Speak Freely. It is very similar to other Vo. IP software packages (such as Microsoft Net. Meeting and Vocal. Tec Iphone) except. . . It runs under Linux. • Linux is used for IRLP because it is reliable, programmable, efficient, and functional.

The Vo. IP Concept for IRLP 1. Sample the audio using an analog to digital (A/D) converter. The A/D converter used is a standard PC sound card. This creates a 8 -bit digital stream of raw audio. 2. Compress the audio by using an 8 bit algorithm to reduce the size of the stream by a factor of two.

3. Split the stream into packets. 4. Transmit the packets. 5. Uncompress the packets into an 8 -bit raw audio. 6. Play the audio stream through a digital to analog (D/A) converter (your sound card).

Some Interesting Nodes Others can be found at: http: //status. irlp. net/statuspage. html • • • • 2040 2050 4970 5470 5515 5600 6800 6950 7000 7995 8700 8880 VE 2 CRA VE 1 NSG WA 1 ZVZ 8 P 6 AW MM 0 GEQ DB 0 VOX GB 3 LV VK 8 ZMA ZL 1 BQ J 73 D VP 9/VE 3 KXX ON 0 GRC KC 4 USV Ottawa Canada Halifax Canada Merritt Island FL Bridgetown Barbados Edinburgh Scotland Nuremberg Germany London England Darwin NT Australia Auckland New Zealand Roseau Dominica Smiths Parish -- Bermuda Gent Belgium Mc. Murdo Station – Antarctica

Idaho Falls NODE 3372 Currently, there is just one IRLP node here in Idaho Falls: • 446. 500 (100 hz Tone Required) Red Lion Simplex • 14 x. xxx Red Lion (in the very near future!) This will require a tone as well and will be Simplex.

Common Error Messages “The node you are trying to connect to is being used locally. ” The node you are trying to connect did respond because it’s being used locally. “The call attempt has timed out the connection has been lost. ” The node called is NOT responding. The Internet retry count might have exceeded limit. The node is temporarily off-line. “The connection has been lost. ”(During a conversation) The Internet retry count might have exceeded limit. The node has temporarily gone off-line. The Internet might be very busy and causing excessive message delays. The other end terminated the link. ”Busy Audible Tones” The node you are trying to connect to responded, however it’s currently in use. You can check the active node status page to see where it is connected. Ø Visit http: //status. irlp. net/ “The node you tried to call does not exist. Please check the code and try again. ” You entered an invalid four digit node number. For additional information visit http: //www. irlp. net/

Equipment on the Red Lion • • UHF - Alinco DR-435 T Dell Computer VHF – Radio still to be determined Microtel Computer