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ISS ham status 11/9/2000

Space Station Alpha given permission to assemble the Amateur Radio

November 9, 2000

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

The first full time crew for ISS ALPHA has docked and moved in.
One of their first official requests was to give the International space
station a name.
Astronaut Bill Shepeard ask Dan Goldin of NASA for a request on behalf
of the first ISS ALPHA crew.  Bill asked to use the call sign of the
Space station as Alpha. 

Congratulations to Bill Shepherd, Yuri Gidzenko  and Sergei Krikalev for
cutting through all the red tape and giving ISS ALPHA a name.  Let's
hope her name stays and she flies as long as the successful Russian Mir

For more information on this mission please check the NASA web pages.

Space Station Alpha given permission to assemble the Amateur Radio
The ISS crew received permission to assemble the Amteur Radio 2-meter
station this weekend, if time permits.   The crew's workload is still
very high and they may not have time to complete the project until later
in the week.  The plans call for testing the amateur radio station with
a few selected NASA and Russian ground stations to test out the signal
performance.  If all goes well, then the system could be placed in
service for the public to chat with the ISS crew during their off times
on weekends in the near future.  The Amateur Radio system also includes
a simple email system called packet  mail.  The packet system can be
used to send and receive email from earth and will be open to all
licensed amateur radio stations.  The system uses standard AX.25
1200-baud packet.  The TNC as is it called has its own CPU and 32k of
memory for mail storage.

ISS Alpha VHF / UHF radio links:
The ISS uses three different types of communications links to earth:
VHF Ground Relay stations
S-Band commercial satellites
TDRS NASA satellites

The Alpha crew has been using the old MIR VHF and UHF radio links to
communicate with Mission control.  The VHF link is usually active while
the ISS is orbiting over North America and Russia.  There are
approximately 9 VHF Ground Relay stations in operation (6+ in Russia and
3+ in the USA).  When ISS passes in range of a Ground Relay station, it
is connected to Mission control in Russia.  The VHF / UHF links are used
for voice and low speed data only.  During a typical 90 minute orbit,
the ISS will typically have less than 20 minutes of communication time
with Mission control per orbit.  If you are watching the NASA channel
with the world map displayed, the circles over North American and Russia
are the Ground Relay stations.  The ISS can only communicate over the
VHF links while it is inside one of those circles.  The Amateur radio
community in Europe and the USA have been having fun listening to ISS
via the direct VHF links.  When ISS is over the Indian Ocean and pacific
oceans, it is usually out of communications range of all Ground Relay
stations.  Note: I do not post the ISS commercial frequencies.

S-Band commercial satellites:
The ISS has also been intermittently using an S-Band commercial
satellite to pass voice and high-speed data, when ISS is over Europe. 
Last week we saw the ISS crew using a PC videophone using the protocol
H.323 Video.  The image quality was quite good, and I assume there were
running QCIF at 768kbit.  The new video standard will eventually migrate
to Amateur radio in the form of Compressed Digital Amateur TV (CDATV). 
More on this topic in the future.

TDRS NASA satellites:
The ISS crew has not installed the Antenna needed for the TDRS links. 
The new antenna will be delivered and installed next year.  After the
TDRS link is working, the ISS will have over 70% link coverage to
Mission control with both voice and high speed data.  The web page below
will describe how TDRS works.  New satellites will be added in the
future to bring up the orbit coverage to over 95%.


International Space Station Alpha Amateur Radio Call signs:
The ISS ALPHA is keeping the international flair by hosting several
amateur radio call signs from around the world.  So far the ISS ALPHA
has three calls signs from three different countries, Russia, USA and
Germany. Also each of the crewmembers of expedition 1, has their own
personal Amateur Radio call sign.

William Shepherd, Expedition commander, KD5GSL
Yuri Gidzenko, Soyuz commander (unknown)
Sergei Krikalev, flight engineer, U5MIR 
Russian Module call sign:	RZ3DZR
Other club call signs ISS used: NA1SS and DL0ISS ALPHA

Ground Station:
What will you need to Hear the ISS ALPHA Amateur Radio 2-meter Station.
That's a tricky question because there are good orbit pass and poor low
orbit passes.  On a good 45 degree orbit pass, since the ISS ALPHA is
only 250 miles high, you will be able to hear the 2-meter signal from
the space station with a very small antenna (0 dBd  to  minus 12 dBd
(rubber duck)).  During a very low orbit passes under 20 degrees you may
need a much larger antenna.
The Amateur Radio station on ISS ALPHA will be transmitting in the
satellite 2-meter band (ITU 144.000 - 146.000 mc).  I have listed a
frequency chart below.  The ISS ALPHA transmitter power output is
approximately 3 watts, into a vertical antenna rated at minus 3 dBd.  I
do not have the coax loss values at this time.  This combination of
power and antenna gain will provide an ERP rating of  approximately 1.5
watts.  The 1.5-watt value is not that bad, I was able to hear the
RS-17/18 satellites from my car antenna (minus 3dBd) and those
satellites were only running 0.5 watts.  If you only have a zero dBd
gain antenna and a police scanner you will still be able to hear the ISS
ALPHA on some good orbits.
(note:  if your antenna is rated in dB rather than the correct dBd
value, subtract 3 to convert the dB value to the correct dBd rating)

Suggested receiving station:
Casual listening for ISS ALPHA and Mir
2-meter vertical or scanner antenna (0 dBd or better)
Police scanner or amateur radio with the ability to receive in the 144 -
146 mc or MHz range, FM mode.  Antenna cable should be a low loss RG-8
style cable less than 100 feet long (RG-213 best choice).  You will not
need to mount the antenna very high, just try to get above the roof
ridgeline.  And of course you will need to find / buy a satellite
tracking program.  I recommend the InstantTrack 1.5. It's a simple easy
to use program, which can be purchased from Amsat.

ISS ALPHA frequencies:
The Amateur Radio frequencies for ISS ALPHA have been posted.
Worldwide downlink for voice and packet: 145.800
Worldwide packet uplink: 145.990
Region 1 voice uplink: 145.200
Region 2 & 3 voice uplink: 144.490

You will need to dig out the manual for your radio and program in the
following frequency combinations.  Note that some of the older FM mobile
and Walkie-talkie HT style radios over 15 years old may have some
difficulty in saving these combinations into memory.  The channels
listed below will help you compensate for the speed of the space
station, called Doppler.  If the smallest channel step your radio
supports is 5k, then only program in channels 2, 5 and 8.  If your radio
supports the smaller 2.5k channel step, then program in all channels
listed.  After you have determined your smallest channel step supported
by your radio, then program in the channels.  You can either use the
procedures for storing ODD-Splits or you can reprogram your repeater off
set for each of the channels and then save the new combination in a new
memory location. This channel procedure has been successfully used on
the Mir Amateur Radio program for years and is the choice of usage for
school schedules (you do not want to fiddle with VFO's during a
10-minute pass).  I also recommend you program in all channels, no mater
what part of the world you live in.  The World Map ISS ALPHA location
display used by the ISS ALPHA crew is not located next to the Amateur
Radio station. 

Voice operations Region 2 & 3 (North and South America and Pacific)
Chan	Receive	Transmit	Offset (Meg)
1	145.802.5	144.488.5	-1.314
2	145.800.0	144.490.0	-1.310
3	145.798.5	144.492.5	-1.306

Packet operations Regions 1, 2 & 3 (Europe, North and South America and
Chan	Receive	Transmit	Offset (Meg)
4	145.802.5	145.988.5	+0.186
5	145.800.0	145.990.0	+0.190
6	145.798.5	145.992.5	+0.194

Voice operations Region 1 (Europe)
Chan	Receive	Transmit	Offset (Meg)
7	145.802.5	145.198.5	-0.604
8	145.800.0	145.200.0	-0.600
9	145.798.5	145.202.5	-0.596

Usage Example:
Lets assume ISS ALPHA is approaching for a good 10 minute over head
pass, running Packet.  When ISS ALPHA comes over the horizon the Doppler
frequency error will initially be 3.5k plus 145.990 = 145.993.5.  This
means the frequency ISS ALPHA will appear to be transmitting on is
145.993.5.  Set your radio to channel #4 for the first 3 minutes of the
pass.  Then for the next 3 minutes use channel #5 and for the last three
minutes use channel #6.  Follow the same procedure for Voice
operations.  Since we are using the Mode FM, we do not have to have our
Transmit and receive frequency exactly on frequency. We can be off
frequency 1-2khz and still get reliable Voice and Data.  The MAREX-NA
team has been using this procedure for 10 years with excellent results.

QSL card:
A QSL card is a post card, which you can request to confirm you made a
two-way or heard the crew on the Amateur Radio band.  The QSL procedure
for ISS ALPHA is under development, please check the AIRSS web pages for
the latest updates and QSL procedures for ISS ALPHA.
http://arISS Alpha.gsfc.nasa.gov/

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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