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Re: "Size" of satellite

PostPosted: Mon May 02, 2011 8:01 pm
by DaveHein
Transmitting one beep per orbit would make detection very risky. You would have to ensure that your satellite passed over a populated area at the time it transmitted it's beep each orbit. Given that most of the world is covered by oceans, it would be difficult (if not impossible) to follow an orbital path that would achieve this. A duty cycle of 10% should be achievable with a battery weighing less than a 2 grams.

Re: "Size" of satellite

PostPosted: Mon May 02, 2011 8:12 pm
by rick m
That was my interpretation, a single beep once per orbit would do though I was planning on a few beeps in case one might be missed. But, I didn't think of simply launching nine sub-orbitals over head (hard to do with sugar since it makes such a huge exhaust trail easily seen for miles). Maybe just nine balloons or nine of our small "smoke-less" hybrids...hmmmmmmm thanks Paul, I think we can be ready next week for that.

Re: "Size" of satellite

PostPosted: Mon May 02, 2011 8:30 pm
by rick m
This reminds me of a plan I had in my younger days to fly a very high kite at night over the NRAO VLA at Socorro and transmit some "alien" signal.

Re: "Size" of satellite

PostPosted: Tue May 03, 2011 3:58 pm
by DaveHein
Look at the attached image file that shows the satellite path for 9 orbits if launched from 45 degrees north latitude. The radio signal will be received within a few hundred miles of the fly-over path using omni-directional antennas. Radio receivers will be needed around the world to verify the orbit. I think the best approach would be to use the network of amateur radio operators to help detect the signal. The time and location of each reception would provide verification of the orbit. The signal would need to be transmitted a few times per minute for this to work.

In the orbital path I show, the first orbit will pass over South Africa and Australia. If a signal is detected at one of these locations the remaining orbits can be predicted, and the HAM community can be alerted to the expected time and direction for fly overs at their locations. This would allow them to use higher gain directional antennas so that the signal can be received from a thousand miles on either side of the satellites path. The duty cycle or power could be reduced for subsequent orbits. Of course, there is the risk that signal would not be detected on the first orbit, and a higher duty cycle or power would be needed on a later orbit to locate the satellite.

Re: "Size" of satellite

PostPosted: Sat Jan 18, 2014 1:30 pm
by rick m
Going out to the FAR site http://friendsofamateurrocketry.org/ today to test our satellite...weighs in at 8 grams.

Then tomorrow we'll be working on our 2-stage at Jeff Jakob's place. Monday we are planning a test flight to 33,000 meters over the Mojave.

Rick