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ISS Amateur Radio Antenna status report

ISS Amateur Radio Antenna status report

May 25, 2000

By Miles Mann WF1F,
MAREX-NA (Manned Amateur Radio Experiment, North American Division)

The long and short term plans for Amateur Radio antennas on the
International Space Station (ISS) are progressing very well.  It was
originally proposed in 1996 by RSA Chief of the Amateur Radio
Cosmonaut Department, Sergej Samburov, to use a temporary navigation
antenna on ISS for the initial antenna for Amateur Radio experiments. 
And then after a few space walks,  a dedicated group of antennas for
Amateur Radio experiments could be installed.  This plan seems to be
working.  The Russian Zarya Control Module, also know as the Functional
Cargo Block (FCB) is currently in orbit and connected to the NASA Unity
module.  There is an existing externally mounted antenna on this module
which was used for telemetry.  Now that the Zarya module is in orbit,
the telemetry antenna is now available for other uses.  I was told by
RSA that the antenna is tuned for approximately 147 mc, which is perfect
for the Amateur Radio satellite band 144.000 - 146.000 mc.
When the first ISS crew moves in later this fall, they will have
immediate access to this antenna port from inside the Zarya module, No
space walk will be required.  The only limiting factor, is when will the
ISS crew be allowed the time to install the amateur radio voice/packet
station.  The ISS crews time line (or work load) is calculated down to
the minute.  You are even assigned times to go to the potty.  During a
recent visit to the European Space Agency, one  person said the ISS
crews would use the Amateur Radio station during their Free time.  Then
another ESA representative then said, There is no such thing as Free
time for the crew while in space.  All of there time is scheduled.  

Since the Zarya module antenna is limited to the 2-meter band, there
will only be 2-meter mono band access for the first year.  This is
actually good news for beginners, since it is much harder to work Split
band 2m/70cm.  The original ISS 2-meter system will operate both FM
voice and 1200 baud AX.25 packet.  This is the same packet protocol used
on Earth for your local BBS access.  This is also the same packet format
used on Mir, however some of the commands may be different.  The Zarya
module 2-meter radio will be limited to approximately 5 watts of
output.  If you have a zero gain antenna, you will be able to get access
on a few passes per day.  A real gain directional antenna system will
improve your link reliability.

Here is a NASA link for the proposed time line.  

When will the Amateur Radio Station on ISS be turned on?
That's a good question. The best guess is a month or two after the ISS
crew moves in. Sergei Konstantinovich Krikalev is part of the first ISS
crew.  Sergej is a real Ham.  He knows the importance of Amateur Radio
for long duration Missions.  I am sure he will do his best to get the
system on line in a reasonable amount of time (crew work load and
permissions permitting).

Next Antennas:
The engineers at RSA really did a great job in planning for additional
antennas on ISS.  The Service module has 4 extra multi purpose antenna
ports installed.  Each one of these empty antenna ports can be used
simultaneously for commercial and amateur radio access.  The
simultaneous access is achieved by properly filtering the signals which
allows 2-3 different signals to share a single antenna port.  Service
Module Antenna port 1 will have three antennas diplexed into one cable,
supporting Amateur Radio bands 2-meters and 70 centimeters and a
commercial 2.4 gig band.  Amsat Italy designed the triband antenna for
port 1.  I do not have any data on ports 2-4 at this time.  The Service
Module is scheduled to be launched this summer (Aug 2000).  The new
ports are just empty antenna feed through ports.  There are no antennas
connected to the ports before launch.  The antennas must be installed
after docking via a space walk.  The space walks to install the Amateur
Radio antennas are not scheduled until the Summer of 2001.  The 2.4 gig
commercial port will be used to receive TV signals from crews during a
space walk (just like in the movie Aliens).  Each crew member will be
wearing a TV camera attached to his helmet.  It may be possible to hams
to hear the weak 2.4 gig signals live, that is if you have 24 dbd of
antenna gain on 2.4 gig.  After the new antennas are installed in 2001,
we will be able to connect additional Amateur Radio experiments to these
ports.  The service module has some cabinet space reserved specifically
for Amateur Radio experiments.  The MAREX-NA team is actively developing
a software version of Slow Scan TV for use on ISS.

See you on Mir and ISS

MAREX-NA home page

Copyright 2000 Miles Mann, All Rights Reserved.  This document may be
freely distributed via the following means - Email (including
listservers), Usenet, and World-Wide-Web.  It may not be reproduced for
profit including, but not limited to, CD ROMs, books, and/or other
commercial outlets without prior written consent from the author. 
Images received from the MAREX-NA SSTV system on the Russian Space
Station Mir are considered public domain and may be freely distributed,
without prior permission.

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