[amsat-bb] Re: Bill Ress - N6GHz - Board Candidate - OperatingSurvey
glasbrenner at mindspring.com
Tue Jul 22 05:11:56 PDT 2008
Some replies to Ed's comments:
> The Intelsat should be much less expensive:
> 1-free ride
> 2-free power
> 3-free stabilization
Let me clarify this some. It is -not- a free ride. Intelsat will charge us
for the loss of operational time for every kg of stationkeeping fuel they
offload to accomondate our extra mass. There may be some recurring expenses
> All you provide is RF, antennas, and a communication processor.
The good stuff.
> But the location is specified by Intelsat so only one-third of the earth
> is covered. Which third do you chose for satellite #1. For whole-earth
> coverage you need rides to three locations 120-deg longitude apart. Far
> north latitudes will probably not get coverage due to low angles to GEO.
> For my location at 60.7 latitude the GEO path is 21 degrees elevation due
> south and is lower as you move east or west.
We most likely would not be dealing with any sort of spot beam and the
antennas should be broadbeamed enough so that there is no reason to assume
1/3 instead of almost 1/2. If you could work AO-10, AO-13, or AO-40 near the
horizon, the same would likely be true for Intelsat. What would be different
is we each could dedicated a fixed antenna with no rotor for ground side,
and if you live surrounded by 100' pine trees like I do, you can find an
open hole to point through.
> So continuing with Eagle offers world coverage over a couple days of
> orbiting. GEO stays in one position.
While this will maybe make some DXers feel less fulfilled than a HEO, it's
my hope that it will attract 10x their number in other users. A GEO knocks
500$ of the top of everyone's station budget right out of the gate...no
az-el rotor. Think of the traffic that is likely to be attracted to
this...24/7 amateur coverage with set and forget antennas over 1/2 the
earth. No Doppler tuning. Practically fixed gain requirements. We may have
to find a way to manage the data and repeater system links that will
inevitably show up. My gut suspicion is we won't be able to afford enough
bandwidth on the first iteration for the users that may come out of the
woodwork. If we could just get all the users to support the program...
> I will see you in Anchorage, Drew!
The YL and I will be in Anchorage on Saturday evening, then in Seward and
Whittier until Thursday or so. I'm looking forward to meeting and speaking
with all of ya'll!
73, Drew KO4MA
More information about the AMSAT-BB