Hi all.
Deployable gain antennas are possible, but unfortunately attitude control is a real issue. If the orbit has a high perigee then the magnetic field for magnetorquing is minimal. With limited fuel and little or no magnetic field, keeping the antennas pointing correctly is difficult. Also, all of this getting to HEO is challenging given our lack of experience with low mass / ion propulsion. A compromise could be 4 Watts (ish) from MEO. That can be done with omnidirectional antennas, so when the batteries die and the fuel is exhausted we still have a useful satellite even if we cannot control attitude.
Would be great to team up with a group who want to test a propulsion system and apply for a launch opportunity.
Thanks
David
Here's an oldie but goodie..... http://www.g0mrf.com/MEOSAT.htm
-----Original Message----- From: Joe nss@mwt.net To: amsat-bb amsat-bb@amsat.org Sent: Tue, 30 Apr 2013 17:18 Subject: [amsat-bb] Re: Path to HEO
On the Outside? :-)
just like 90% of the earlier birds they are rolled or folded up until after deployment. IIRC: one of the first actually did use a rolled up tame measure for the elements.
Joe WB9SBD Sig The Original Rolling Ball Clock Idle Tyme Idle-Tyme.com http://www.idle-tyme.com On 4/30/2013 9:51 AM, Andrew Glasbrenner wrote:
Where do the gain antennas go on a 10x10x30cm HEO?
73, Drew KO4MA
Sent from my iPhone
On Apr 30, 2013, at 9:01 AM, N0JY n0jy@lavabit.com wrote:
I wonder about the amount of time spent in the Van Allen belts on
the way up there. We're concerned about radiation at a 650 km orbit, it might take some heavy duty ($$) radiation tolerant components to survive a few years trip through the radiation belts as well as the final high orbit?
Jerry N0JY
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