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Re: Six Amateur Radio Satellites to Launch in March



---------- Forwarded message ----------
From: Bruce Robertson <ve9qrp@gmail.com>
Date: Jan 16, 2008 2:07 PM
Subject: Re: [amsat-bb] Re: [SPAM] Six Amateur Radio Satellites to
Launch in March
To: David - M0ZLB <m0zlb@btinternet.com>


David (and JoAnne):

Cubesats seem regularly to elicit a kind of nostalgic sadness amount
some of us, of which I consider your letter a representation. Like
you, I take great pleasure in working other amateurs on voice or CW
using satellites equipped for such operations; like you, I'm a bit in
mourning for FO-29. However, I respectfully suggest that there might
be a more hopeful, and ultimately more enjoyable, response to the
current situation in LEO. I hope you don't mind me engaging these
issues on the list in the hopes of fostering understanding in our
corner of the hobby.

I think this sadness is based in three ideas commonly held about
cubesats which I would like to dispell. The first is a sense that we
have declining prospects for linear communications in LEO if the
number of prospective digital or one-way birds far exceeds the number
of linear ones. Now, with the growing popularity of cubesat projects,
it is clearly the case that a whole whack of digital and one-way
digital birds are going up. But given that our bands are not being
congested by them, this does nothing to reduce the number of linear
project.

In fact, we have a healthy roster of up-coming linear projects:
KiwiSat, and the Chinese CAS-1
http://www.southgatearc.org/news/october2007/chinese_amateur_radio_satellite.htm
for example.The Indians are talking about a second Hamsat. There
should be much fun to be had in this area in the future. I'm not sure
if any of these have prospects for a higher orbit like FO-29, but
under the conditions as JoAnne outlined them, this has nothing to do
with if or if not the cubesats fly.

The second misconception is that a typical cubesat's mission is
somehow tangential to the real purpose of the amateur satellite
service. However much I would like each and every one of this cubes to
carry a linear transponder -- because I like chatting with other hams
through orbiting satellites -- I can't help but conclude that the
Cubesats are doing very important work. Imagine telling the builders
of OSCAR-1 that they're bird is not in the Amateur Service! Imagine
telling them that in 50 years' time not only would there be a clutch
of communications satellites for hams, but also university students
around the world would collaborate with hams to operate birds that
download pictures from orbit and conduct other experiments. Would they
be disappointed? Or would they see these missions as wonderously
fulfilling the promise of OSCAR-1?

A third misconception is that digital operations (in which almost all
cubesats participate) are difficult to undertake and also tangential
to the amateur sat. service. Using radio to remotely control and
communicate with a device that is orbiting the earth every 90 minutes
from 100 miles up is a brilliant use of the radio service!
Furthermore, it's pretty darn easy: 1200 bps AFSK can be read with a
soundcard and a $99 HT; in fact, if you have a all-mode all-band
radio, as cheap as the FT-817, the easiest bird to hear of all is
LO-19, whose CW dialect booms in on my indoor quarter-wave whip.

I can imagine that folks might think this is not exciting to do. I
have found that regular telemetry collection can be very interesting
and engaging, perhaps more like amateur astronomy than linear
operations on the birds. If you want exciting, join the chat line in
the days after a cubesat launch: teams of sleep-starved 20-somethings
desperate for news of their Darlings in Space. Imagine the chance to
be the first to report healthy telemetry from a new orbiting object.
It really is a great time to participate, and it takes quite a bit of
technical skill: I've come to admire Mineo's JE9PEL setup and that of
Mike DK3WN as they routinely hear things first off the blocks.

As for the current launch manifest, in fact, it can be argued that
Delfi-C3 represents a remarkable benefit to linear operators that
comes from the cubesat world. Rather than a disappointing singular
example of a linear bird among the upcoming cubesats, it should, I
believe, be taken as an example of what we have to gain from this new
age of LEO building and launching. When before has the amateur service
been effectively *given* a bird which will eventually be in linear
service, with no appeal for launch or building costs? How can we
ensure that others will do the same? We should shower the Delfi team
with gratitude by giving them as much high-quality data as possible.
After all, their research has direct bearing on our future work, too.

But Delfi-C3's transponder is ground-breaking in another way: it
pushes linear LEO satellites quite far down the cost/power curve. If
this provides reliable comms. to those of us with modest az/el yagi
setups, I think you will find other regional amateur teams jumping on
the cubesat format for linear comms. at a very reasonable launch price
(what, launch at $40,000 per cube?) Even more exciting is the prospect
that university groups will team with AMSAT subgroups to make
something like Delfi-C3: say, we hams will provide the comms for your
digital mission, and then in a year we get a linear transponder. Based
on the mission success of Delfi-C3, you can be assured that you'll get
tons of data.

Then there are amazingly clever ideas like Sat on a PCBoard and
Dragonfly. Both of these ask the question, "how little power can we
get away with in orbit, given the improving base stations?"

Obviously this has gone far beyond a reply to David's letter. I hope
it will be taken in the spirit it was written: as an encouragement
toward excitement. Heraclitus said, a man never walks through the same
river twice; similarly, we never will launch the same birds under the
same circumstances. But with the right attitude the river is always
beautiful and exciting, and so will be our hobby.

73, Bruce
VE9QRP


On Jan 16, 2008 8:23 AM, David - M0ZLB <m0zlb@btinternet.com> wrote:
> Thanks for the links Bruce, I too couldn't find any frequency info after
> Trevor's initial posting!
>
> Sadly I see that with the exception of Delfi, everything else is digital.
> Surely it is imperative that we get more easy sats up there for the newbies
> to cut their teeth on and then progress! With the loss of FO-29 to virtually
> everyone out of the JA footprint, its becoming a specialised hobby - there
> is a need to get back to basics here I would have thought!
>
> David
> KG4ZLB
> AMSAT UK
>
>
> Bruce Robertson <ve9qrp@gmail.com> wrote:
> I think what seems to be rubbish to you is directed at different
> audiences: the local media, colleagues in the university and funding
> organizations, for example, none of whom are interested in
> frequencies.
>
> Happily, we hams have the summarizing website of Ralf Wallio, W0RPK,
> http://showcase.netins.net/web/wallio/CubeSat.htm
>
> Frequency information is also available from IARU:
> http://www.amsat.org.uk/iaru/
>
> 73, Bruce
> VE9QRP
>
> On Jan 16, 2008 6:54 AM, Andrew Rich wrote:
> > I wish some of these sat launchers would put as much effort into their
> > webpages as their satellites.
> >
> > Most don't list frequencies and seem to me to be a completer afterthought.
> >
> > I get frustrated searching page after page of just rubbish to turn up
> > nothing.
> >
> > Enlighten me
> >
> >
> >
> ----------------------------------------------------------------------------
> > Andrew Rich VK4TEC
> > vk4tec@people.net.au
> > http://www.tech-software.net
> >
> >
> >
> >
> >
> > -----Original Message-----
> > From: amsat-bb-bounces@amsat.org [mailto:amsat-bb-bounces@amsat.org]On
> > Behalf Of Trevor
> > Sent: Wednesday, 16 January 2008 6:16 AM
> > To: AMSAT BB
> > Subject: [SPAM] [amsat-bb] Six Amateur Radio Satellites to Launch in
> > March
> > Importance: Low
> >
> >
> > It looks like they'll be six Amateur Radio satellites launching in March
> > including Delfi-C3, see
> >
> > http://www.uk.amsat.org/
> >
> > 73 Trevor M5AKA
> >
> >
> >
> > __________________________________________________________
> > Sent from Yahoo! Mail - a smarter inbox http://uk.mail.yahoo.com
> >
> > _______________________________________________
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> >
> > _______________________________________________
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> >
> _______________________________________________
> Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author.
> Not an AMSAT-NA member? Join now to support the amateur satellite program!
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>
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