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Re: New AO-27?



Robert wrote: {edited}
>Let me try.
>
>A AO-27 over the US?  IMagine one repeater for the entire US that one single 
>person could/would use/monopolize at a time.  Now allivaite that problem by 
>only the additional channels that you add to the system.
>
>See now that wasnt hard.  Was it?
>
>There could be more to the answer like one might look at the UHF-follow ons 
>to see how such a system might operate but then again the person might not 
>know what the UHF follow ons are.

{with all the strong opinions and remarks, I'm almost afraid to post this,
now} {Jon: that was a good reveiw on geosync. sats, but I did not get the
impression that Tim was talking about a geo-sync, multi-channel, AO-27.
But still glad you went over it.}  OK, once more into the breech-->

I can think of some other arguments for not making our next satellite
another FM-Leo like AO-27, UO-14, SO-35, ...   

This the first reason: we currently have several FM-Leos for use, but only
one old tired out phase-3, high orbit, AO-10 with dead battery and
controller.  Of course, AO-40 may yet be rescued.

I would guess the time, effort, and expense of building an FM bent-pipe Leo
is nearly the same as a single-mode passband bent-pipe satellite {not
exactly but lets put the effort... where there is the greatest need}.
Launch expense and opportunities are about equally hard {I'm not talking
about another P3D, but a trimmed down version more like AO-10; or even
simpler}.

There is no comparison between a relatively "arm-chair" QSO of 30+ minutes
on a phase-3 satellite vs, the hectic "tune the radio"-"move the
antenna"-"talk fast" operation on the Leos.  BTW standing outside with a
dualband HT and an Arrow antenna in -30 degree winter weather in Alaska
might cure a lot folks of this mode!  Sure, you can auto-tune your radio,
and auto-track your high-gain antenna system {for $$$}, but it isn't
required for high orbit satellites like AO-10, 13, and 40.  

Imagine talking to other side of the world...not on a Leo!

I lived in the Alaskan "Bush" in the mid-1980's when I worked AO-10 a lot.
Had not electricity, running water, heated with wood, and operated using a
deep-cycle battery re-charged with a gas generator.  My Cushcraft 20T and
416 were mounted on a hinged crossboom so that elevation was controlled by
a cord run thru a pulley and azimuth rotated by hand.  I only needed to
adjust it every 30 minutes or so.  Try that with a Leo?

I think maybe many hams' experience with satellite operation is limited to
operating the Leo's so they may not have the benefit knowing of what an
amazing difference in the experience there is working the phase-3 type!

Final argument:  How many QSO's are supported on 1,2, or 3 FM channels vs
100 KHz of spectrum? 

So my vote is for a high-orbit, mode U/V or L/S satellite {or both if
possible}.

Ed
Hoping that AO-40 will be back and make this purely rhetorical ;-)  {sorry
for repeating some of the points}
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