LESSON 23

Voice communications, EchoLink and IRLP

Voice over Internet protocol(VoIP) is used for two types of amateur radio related operations, these are Echolink and Internet Radio Linking Project abbreviated IRLP.

Echolink is a Microsoft Windows computer program which allows, for at least part of the communication path, amateur radio operators to communicate with each other via the internet VoIP. An amateur radio license is the only requirement to use the Echolink system.


IRLP uses a worldwide network of dedicated servers and nodes to provide an inexpensive yet reliable way to link amateur radio systems using ViIP and the internet without the use of RF links, leased lines, or satellites. It will allow a simplex station or repeater site to link with other similar sites or to be accessed via computer around the world. Simply put IRLP is a method of linking two or more amateur radio stations together using the internet.

T6B01 (C)
How is information transmitted between stations using Echolink?
A. APRS
B. PSK31
C. Internet
D. Atmospheric ducting
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T6B02 (A)
What does the abbreviation IRLP mean?
A. Internet Radio Linking Project
B. Internet Relay Language Protocol
C. International Repeater Linking Project
D. International Radio Linking Project
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T6B03 (B)
Who may operate on the Echolink system?
A. Only club stations
B. Any licensed amateur radio operator
C. Technician class licensed amateur radio operators only
D. Any person, licensed or not, who is registered with the
Echolink system
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T6B04 (A)
What technology do Echolink and IRLP have in common?
A. Voice over Internet protocol
B. Ionospheric propagation
C. AC power lines
D. PSK31
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T6B05 (C)
What method is used to transfer data by IRLP?
A. VHF Packet radio
B. PSK31
C. Voice over Internet protocol
D. None of these answers are correct
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T6B06 (B)
What does the term IRLP describe?
A. A method of encrypting data
B. A method of linking between two or more amateur stations using the Internet
C. A low powered radio using infra-red frequencies
D. An international logging program.
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T6B07 (B)
Which one of the following allows computer-to-radio linking for voice transmission?
A. Grid modulation
B. EchoLink
C. AMTOR
D. Multiplex
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T6B08 (C)
What are you listening to if you hear a brief tone and then a station from Russia calling CQ on a 2-meter repeater?
A. An ionospheric band opening on VHF
B. A prohibited transmission
C. An Internet linked DX station
D. None of these answers are correct
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T6B10 (C)
Where might you find a list of active nodes using VoIP?
A. The FCC Rulebook
B. From your local emergency coordinator
C. A repeater directory or the Internet
D. The local repeater frequency coordinator
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T6B11 (D)
When using a portable transceiver how do you select a specific IRLP node?
A. Choose a specific CTCSS tone
B. Choose the correct DSC tone
C. Access the repeater autopatch
D. Use the keypad to transmit the IRLP node numbers
~~


RESEARCH

ECHOLINK
Echolink is a computer program that runs under Microsoft Windows to allow radio amateurs to communicate with one another using Voice over IP (VoIP) technology on the internet for at least part of the path between them. It was designed by Jonathan Taylor, a radio amateur with callsign K1RFD.
The program allows reliable worldwide connections to be made between radio amateurs, greatly enhancing Amateur Radio's communications capabilities. In essence it is the same as other VoIP applications (such as Skype), but with the unique addition of the ability to link to an amateur radio station's transceiver.
Before using the system it is necessary for a prospective user's callsign to be validated.
Radio amateurs using the Echolink software can operate it in one of two modes:
• Single User Mode. If they have an internet-connected computer, they can use the computer's microphone and speakers to connect to (or through - see below) other Echolink-enabled computers over the internet and talk to the amateur at the other end.
• Sysop Mode. This entails connecting their own VHF or UHF transceiver to their internet-connected PC with a specially-designed hardware interface. Doing this enables another radio amateur with their own transceiver, who is within radio range of this station, to communicate with (or through) any other Echolink-equipped station anywhere in the world. This is the unique feature of Echolink.
Radio amateurs without the Echolink software or a computer connected to the internet can take advantage of the Echolink network if they are within radio range of a sysop mode Echolink station. It is also possible to link a sysop mode Echolink station to a local repeater, further enhancing the communication possibilities.


Internet Radio Linking Project

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 your repeater site or simplex station to the world in a simple and cost effective way.
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.