ARISS-Europe News Bulletin – 22.07.2006
ARISS SCHOOL CONTACT WITH THOMAS REITER - ECHOLINK AND IRLP INFORMATION
Saturday 29 July 2006 at 12.27 UTC, ARISS will set up a live space
talk for ESA Space Camp in Patras, Greece with German
astronaut Thomas Reiter, DF4TR presently onboard the
International Space Station.
There are no daylight passes of the ISS over Europe that day. Consequently, the radio contact
will be performed by ARISS ground station in Honolulu,
Hawaii, operated by Nancy Rocheleau, WH6PN. Signals will be relayed to Greece by telebridge.
The audio of this QSO
will be made available real time and worldwide to amateur radio operators by
means of EchoLink and IRLP.
For those who are not familiar with these
“Voice on Internet Protocol” (VoIP) modes, here is an
introduction to both systems.
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VOIP MODES FOR ARISS SCHOOL
CONTACTS
When conditions do not allow a direct
radio contact between the International Space Station and the school or other
event location, ARISS provides a so-called “telebridge”.
ARISS counts several dedicated ground stations around the
world. When needed, the radio contact is done by one of these ground stations
and the audio signals are relayed by telephone line to the location where the
event takes place.
With the audio from the ISS and the event location being available on this
telephone line (bridge), ham radio operators from the EchoLink
and IRLP ARISS audio feed
teams take the audio from the bridge and
feed it into the IRLP and EchoLink
ham radio systems, to allow ham radio operators around the world to listen to
these contacts live.
ECHOLINK
The EchoLink
system uses VoIP through the Internet to transmit
audio between two or more locations. The
in and out of audio at all EchoLink locations
(nodes), can be done by connecting ham radio transceivers or repeaters to
Windows based computers. Alternatively,
microphones and speakers can be used connected to computers to communicate
through this system without ham radio transceivers or repeaters. In any case, before any node can participate
in such transmissions, a verification is made during the installation of the EchoLink program to ensure that only licensed ham radio
operators can use this system.
The EchoLink
system is designed for easy installation on computers with the Windows
operating systems. It only runs on
Windows computers.
The installation program for EchoLink is available free of charge for downloads from www.echolink.org/ with
good help file information on the installation and use of this program.
The ARISS EchoLink audio feed team feeds the audio from bridge
contacts into the following two servers, called “Conferences” in EchoLink speak:
AMSAT (node 101 377)
JK1ZRW ( node 277 208)
These two servers allow for many EchoLink nodes to connect to them at the same time. Please give JK1ZRW
your preference during such audio feeds to keep the load light on the AMSAT server.
During audio feeds, text messaging can be
used during ARISS audio feeds, while all nodes
connected to these two servers are being muted (to prevent inadvertent
interfering transmissions). After the
completion of ARISS contacts, all connected nodes
will be un-muted to allow for comments and information exchanges.
IRLP
The IRLP
system, for licensed hams only just as the EchoLink
system, also uses VoIP through the Internet for audio
transmissions between different nodes.
The IRLP system
can only be used by having ham radio transceivers or repeaters connected to
each node. The IRLP
system runs only on computers using the Linux operating system.
To allow for many nodes to participate in
round table conversations, servers have been set up, called reflectors in IRLP speak. Each
reflector can handle many simultaneous connections.
To connect a node to a reflector, most
nodes are set up so that one only has to key in the number of a reflector, e.g.
9010.
The reflector 9010 has been created to
facilitate the distribution of ARISS bridge contact
audio. During such events, simply dial
in 9010 using your microphone touch pad while transmitting on the frequency of
the IRLP node you are using to connect to the
Discovery Reflector 9010. To disconnect
the node you are using from the reflector, dial 73 on your node’s frequency and
you should hear a message that you are being disconnected.
Good information on the use of the IRLP system can be found on www.irlp.net
SUMMARY
We hope that you will find the time to listen
in on some of the ARISS telebridge
contacts. If you need more information
on how to listen and / or when such contacts take place, feel free to e-mail
Dieter kx4y@amsat.org
with ARISS audio feeds in the message title.
As soon as dates and times for upcoming
contacts are known, that information is being posted on the calendar of events
on the AMSAT web site www.amsat.org
If you want to be notified by e-mail of
upcoming ARISS bridge contacts with audio feeds into EchoLink and IRLP, please e-mail
a request to Dieter, KX4Y and he will put you on his
distribution list of listeners.
_______________________________________________________________
ARISS, Amateur Radio on the International Space Station, an
international working group of several amateur radio societies from countries
participating to the ISS, provides a free educational
outreach programme in collaboration with the Space Agencies, involving a team
of volunteering amateur radio operators.
73
Gaston Bertels,
ON4WF
ARISS-Europe chairman