Hmmm, S-band is probably too noisy for the really weak return signal. It might be physically too small for L-band, though that's a pretty quiet place. Maybe something on C-band? C-C Rider on Balloon Bounce?
If this thing works, I wonder how big a balloon we can stuff into a Cubesat? Greg KO6TH > Date: Tue, 29 Jun 2010 00:24:29 -0500 > From: n...@mwt.net > To: amsat-bb@amsat.org > Subject: [amsat-bb] Re: HF Satellite Relay > > Looks like freqs used were right around 2 gig and just above 2 meters > too. according to this book > http://books.google.com/books?id=_azf94TByF8C&pg=PA4&lpg=PA4&dq=frequencies+used+in+project+echo&source=bl&ots=FmCl7J7Mix&sig=eUfFCrcaFQ4lz-5gBS7nt1JLBfg&hl=en&ei=t4IpTOryEsL_nAfjp52MAQ&sa=X&oi=book_result&ct=result&resnum=4&ved=0CCoQ6AEwAw#v=onepage&q=frequencies%20used%20in%20project%20echo&f=false > > Joe WB9SBD > Near Space Sciences > > The Original Rolling Ball Clock > Idle Tyme > Idle-Tyme.com > http://www.idle-tyme.com > > On 6/29/2010 12:03 AM, Greg D. wrote: > > Well, it's finally happened. We've come full circle. They've reinvented > > Echo-1. > > http://en.wikipedia.org/wiki/Project_Echo > > > > Of course, that one was 10x larger. What makes this a 10m (band) > > operation? I expect it would work on the higher bands too, especially with > > the smaller size. What band did they use ~50-ish years ago? > > > > Greg KO6TH > > > > > > > >> From: bruni...@usna.edu > >> To: amsat-bb@amsat.org > >> > > Cancel > > > >> Date: Mon, 28 Jun 2010 13:44:45 -0400 > >> Subject: [amsat-bb] HF Satellite Relay > >> > >> Heard today of a Passive HF relay satellite being proposed. > >> Wondered if Hams could relay off of it. > >> > >> It's a 10m diameter sphere. > >> I assumed a 10m signal and 1000 Watts > >> And antenna gains at both ends of 10 dB. > >> Unless I made a dumb error, it looks impossible? > >> I get a received signal of -170 dBm > >> Compared to a good HF receiver of -122 dBm > >> So its 48 dB down in the noise. > >> Going to narrow band, could improve things, but the Doppler of > >> +/- 600 Hz would make that difficult. > >> > >> Anyway, if someone else wants to double check the link budget > >> using the radar range equation, go for it. > >> > >> The beauty of this system is that it is perfectly spherical, so > >> the reflection coefficient would be constant within 1 dB. That > >> is the advantage over trying to use the ISS or other large > >> rocket body... They vary by 20 dB making communication by > >> reflection impossible. > >> > >> Oh, and it would be in space for 30 years or more. So with > >> something that reliable, it would be worth developing an amateur > >> capability to use it. > >> It is not designed for comms, but as a calibration sphere for > >> over the horizon radars that have LOTS more power and LOTS more > >> gain than we do. > >> > >> Bob, Wb4APR > >> > >> > >> _______________________________________________ > >> Sent via amsat...@amsat.org. Opinions expressed are those of the author. > >> Not an AMSAT-NA member? Join now to support the amateur satellite program! > >> Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb > >> > > > > _________________________________________________________________ > > The New Busy is not the old busy. Search, chat and e-mail from your inbox. > > http://www.windowslive.com/campaign/thenewbusy?ocid=PID28326::T:WLMTAGL:ON:WL:en-US:WM_HMP:042010_3 > > _______________________________________________ > > Sent via amsat...@amsat.org. Opinions expressed are those of the author. > > Not an AMSAT-NA member? Join now to support the amateur satellite program! > > Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb > > > > > > > _______________________________________________ > Sent via amsat...@amsat.org. Opinions expressed are those of the author. > Not an AMSAT-NA member? Join now to support the amateur satellite program! > Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb _________________________________________________________________ Hotmail has tools for the New Busy. Search, chat and e-mail from your inbox. http://www.windowslive.com/campaign/thenewbusy?ocid=PID28326::T:WLMTAGL:ON:WL:en-US:WM_HMP:042010_1 _______________________________________________ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
