---------- 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... 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
73 Trevor M5AKA
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