[Date Prev][Date Next][Thread Prev][Thread Next] - [Date Index][Thread Index][Author Index]

Re: Future ISS amateur radio modes, Marex



Hi Miles, 

think about it, the percentage shift of the carrier frequency of the
modulating tone compared to the carrier will be negligible and therefore the
effect on the tone itself will also be virtually zero. If the Doppler
affected it significantly, our voices through the system would also be
changed significantly. Also, packet wouldn't work either and we know that it
works fine. 

73....Eric VK2VE.

-----Original Message-----
From: sarex-bounces@AMSAT.Org [mailto:sarex-bounces@AMSAT.Org] On Behalf Of
MM
Sent: Wednesday, 2 May 2007 22:42
To: va7to@yahoo.ca; sarex@AMSAT.Org
Subject: [sarex] Future ISS amateur radio modes, Marex

ISS Amateur Radio Status: May 2, 2007

Future Projects on ISS
By Miles Mann WF1F,

MAREX-MG News	www.marexmg.org

Manned Amateur Radio Experiment

Future Projects on ISS:

There are a lot of good ideas regarding how to use
Amateur Radio equipment on board ISS.  I like the
suggestion from Darrell Bellerive va7to of using a
Downlink PL tone from ISS for the voice channel.

I am not sure how much the Doppler will affect the PL
tone.  I am intrigued by the idea and will try some
terrestrial experimentation to if there is much of an
effect.

Current In-flight projects on ISS include:
Packet, Voice (mono-band), Cross-Band Repeater and
SSTV.

Each of these projects has shown good results from
manned platforms such as Mir and ISS.  The projects
that the space agencies like the best are the ones
that do not use very much crew time.  The projects
Packet, Cross-Band and SSTV are the highest bang for
the buck projects because they do not take up too much
crew time. And as we know, free crew time for ham
projexts is very very limited.

Cross-Band Repeater generates a lot if good interest
from the amateur radio community.  There are a few
down side issues to cross band that have to be taken
into consideration.
Not all countries allow amateur radio on the 440 band
(sometimes called 70cm).  
There is more Doppler on 440 (+ and - 10khz)
Some of these and other issues can be overcome with
experience.
I wold be nice if someone could design a small
frequency agile cross repeater that could work on any
combination of 10 meter, 2-meter and 440.  That way we
would have the maximum flexibility based on project
needs.  We have the existing antennas on ISS, let's
use them.

Existing ISS Antenna counts:
Module FGB 	One Sirius 2-meter antenna tuned for
approximately 147 MHZ.  Dual one-quarter wave
co-phased antennas mounted externally.  Currently
connected to the Ericsson Ht.

Service Module, Three Tri-Band antennas, that support
2-meters, 440 and a patch antenna supporting 1.2 - 2.4
GHz.  (The patch antenna has high coax losses,  > 8 dB
at 1.2 GHz)
One 10-meter whip and 1.2-2.4 GHz patch combination.
One of these Tri-Band antennas is conneced to the
D700.  The others are not currenlty used.

Grand total of currently installed Amateur Radio
antennas on ISS
4 antennas for 2-meters
3 antennas for 440
4 antennas for 1.2-2.4 GHz
1 antenna for 10 meters

MAREX is focusing on the entry-level projects for
beginners such as Slow Scan TV and Packet Email.  We
have had excellent results on Mir project with both
SSTV and Packet.  And last summer experimented with
SSTV from ISS with some very good down linked images.

The long term plans, hardware and crew time permitting
is to place SSTV on a 10 meter down link, continuously
streaming images from ISS.
http://www.marexmg.org/imagessstv/SpaceCamImages1.htm

And place a continuous presence Packet Email system on
2-meters, running 24/7.  MAREX has received initial
approval to use a Kantronics KPC-9612 TNC as the data
engine.  This modem supports all the standard features
of most TNC's built, including:
Full Multiple user simultaneous Email users.
Simultaneous dual speed support 1200 and 9600 baud.
Un-proto modes, Text messaging and APRS beacons.

Some unapproved projects Marex is working on are to
provide a full plug and play solution for a new
system.  New style easy to use transceivers, Analog
and digital voice capabilities, Bolt on heat sinks and
fans to compensate for zero gravity cooling issues,
standardized plug in DC headsets and more.  
Your support for these projects would be greatly
appreciated.
http://www.marexmg.org/



ARISS Web page and other great Space projects
http://www.rac.ca/ariss/

73 Miles WF1F MAREX-MG

Until we meet again

DOSVIDANIYA Miles WF1F



__________________________________________________
Do You Yahoo!?
Tired of spam?  Yahoo! Mail has the best spam protection around 
http://mail.yahoo.com 
----
Sent via sarex@amsat.org. Opinions expressed are those of the author.
Not an AMSAT member? Join now to support the amateur satellite program!
Subscription settings: http://amsat.org/mailman/listinfo/sarex

----
Sent via sarex@amsat.org. Opinions expressed are those of the author.
Not an AMSAT member? Join now to support the amateur satellite program!
Subscription settings: http://amsat.org/mailman/listinfo/sarex



AMSAT Top AMSAT Home