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Re:13 Amateur Satellites to Launch in June



Quoting William Leijenaar <pe1rah@yahoo.com>:

> Hi AMSATs,
> 
> Increadible how we can "give away" so many frequencies
> and launches. I just seen the cubesat participation
> list. It is full with universities in US, and other
> countries. There are only 2 amateur participants of
> which stensat is already up...
> 
> Link:
>
http://littonlab.atl.calpoly.edu/media/Documents/Developers/CubeSat_Participants.xls
> 
> That there are many projects going on is not that bad
> at all, its good for future technology. What makes me
> really feel bad is that it is all more looking to an
> indirect commercial business. Just look at the prices
> for such cubesat kit !!!. Its not really an amateur
> price, and it is mainly focused on universities (when
> I see the list of participants)
> 
> I don't feel any "ham spirit" in these kind of
> cubesats anymore. Most (ofcourse some exeptions) of
> those cubes on the list look more like an university
> advertising bleep-box to me... 

William --

I see what you're saying, and as someone who principally enjoys speaking to
others through transponders such as yours, I do wish things were different.
I think there are other points to be raised here, though. 

First, amateur radio activities are frequently 'victims of their own
success'. In more than one field, trail-blazing hams have simplified
technologies and protocols such that less skilled people can undertake
them. Sometimes this means that what would have been originally a homebrew
project becomes one based on a kit or a off-the-shelf product. Cubesats are
just the lastest manifestation of this. 

As I see it, there are two interesting ham responses to this: one is to
push the envelope on today's technology; the other is to put these
commercial and cheap products to amateur use. As a group, I think we're
doing the former with P3E and Eagle, especially the SDR and C-C Rider
aspects. When I joined AMSAT, I never imagined how interesting the articles
in the journal and the discussions here and on the website could be. 

As for the latter, I think the new host of cubesats, though they don't all
support person-to-person communications, do nevertheless represent a group
of interesting space-related experiments, and I'm proud that amateurs
around the world support these with their time and their ground-stations.
If you go to the websites of these projects, very often you will find a
page relating to amateur radio operators and how their help is invaluable.
 In this case, though some aspects of the technology have been simplified,
hams are still part of the loop, participating in the experiment.  


> The reason is that in a real technical way these
> satellites work unefficient in matters of space use. 
> Every cubesat has its own structure, solar, battery,
> and power system etc... Imagine when they all work
> together and put their payloads in one big satellite. 
> Costs would be much lower as they can all share the
> basic systems like solar panels, battery, OBC, etc...
> But ofcourse this doesn't sell much cubesat kits...

I think there would be two responses to this. One is that each team would
very much like to explore all aspects of spacecraft design and control. As
a teacher, I can understand how this might improve the educational side of
the project. The other reply is that the cubesat approach reduces the risk
of project failure. It strikes me that the launcher thingy has a pretty
good track record. After that, each cube is on its own.

> It is also better for students to learn communicating
> with eachother (different universities). In the real
> world knowledge is not always a problem, but
> communication between different engineers and
> companies is... It is even better when working
> together with international schools.

Europe is to be applauded for undertaking this with SSETI Express, and it
should be said that this approach gives us more of a chance for some sort
of ham-specific payload to be tucked on board.

> Maybe there should be made a seperate small "none ham
> funded" cubesat frequency band. It would also be
> reasonable to have a cheaper ham level priced version
> of the cubesat kit for ham-funded projects.

Ok, so here's the thing: many of us would like another linear-transponder
LEO. Cubesats seem to be the sweet spot for price and launch opportunity.
Can we come up with a way to make the cheap technology work for us? Can a
mode U/S linear xponder and all the hardware to support it be built into
10cm square? It seems typical cells produce slightly over 1W, averaging to
450mW available at all times. 
<http://www.space.t.u-tokyo.ac.jp/cubesat/mission/dev/pow/doc-e.html>
I'm guessing it would be pretty darn QRP. Would it require any more receive
antenna gain than, say P3 s-band birds? If not, I think it would be a neat
challenge, and fun to undertake. Maybe we could partner with a university
(or even consortium of high schools) that would like to undertake the
management and control of a bird, but not the payload development. Just
look at the price: $10,000 for the cube and $40,000 for the launch!
http://www.space.com/businesstechnology/technology/050928_cubesats.html

Alternatively, imagine that a 10x10x20 cubesat costs $80,000 to launch
(retail). If we had a 10x10x10 transponder on hand, could we convince a
team that was planning a 10x10x10 cube to go halves with us and let our
transponder take over when their research was done?

These are examples of the second approach I mentioned above. If amateurs
and other have made what was once hard or expensive easy and cheap, let's
use it!

(Of course, AMSAT-NA's focus on HEO is very important. I'm not advocating
getting side-tracked.)

> Just my opinion,
> I better go on with my linear-transponder for the next
> available ham satellite opertunity :o)
> 
> William Leijenaar

Just keep it under 10cmx10cm :-) Seriously, thanks for all your work, and I
hope to communicate through another WL-built transponder soon.

73, Bruce
VE9QRP

----- End forwarded message -----


-- 
Bruce Robertson, 
Dept. of Classics, Mount Allison University
http://heml.mta.ca
----
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