[amsat-bb] Re: Satellite user "communities"

[Edward Cole]

At 10:28 AM 12/12/2007, Bob Stewart wrote:
>With the "range war" that's going on right now, it
>seems like there are at least two communities of
>satellites users: one that wants simple, easy to
>use transponders and doesn't mind the windows
>of availability (and perhaps enjoys it for the added
>simple technical challenge), and another that wants an
>HF band type of experience with perfect propagation.
>There may be other subsets that I haven't noticed, yet,
>but these seem to be the two main groups.  Both have
>their merits.
>
>Bob - AE6RV

Bob,

I by simple you mean single-channel FM Leos and HF you mean linear 
passband Heos...

Well it sounds to me like you haven't worked a Heo.  Working AO-10, 
AO-13 and AO-40 were certainly not "perfect propagation".  Setting up 
a station that will be successful for the old mode-B took some work 
and operating took some skill.  Mode-US was a technical step above 
that of AO10/13.

In comparison to a HT and the Arrow "wave", there is quite a bit more 
technical challenge (in my view) to Heos.
Operating under the current pile-up operating conditions on the Leos 
is no comparison with the ability to hold a round-table of 6-12 
stations that we enjoyed on the Heos.  The point is that there are 
Leos available since AO-40's demise.  AO-7 is the only satellite 
close to being an Heo (and crippled with no battery system and highly 
subject to overload FMing).

The Heo community has shown great patience in waiting a decade for 
AO-40 after AO-13 re-entered and burned up.  Then it only lived about 
3-years with highly reduced performance (though I really enjoyed 
mode-US).  Now we are waiting, again.

P3E and Eagle are needed.  If the only way to get them launched is to 
re-package them for Intelsat piggyback...then that is what we will 
have to do.  Hopefully, rides can be found for P3E and Eagle to 
fulfill their original mission and P4A specific packages built for 
Geostationary service.

P4A concept is the next evolutionary step after P3.  It was long 
thought unattainable, so it is exciting that it may now be more than 
a pipe-dream.
P4A (mode-SC digital voice) offers the restricted apartment dweller a 
real alternative.  It also provides a real opportunity for ham radio 
to fulfill the emergency comms world-wide role that amateur radio 
promises.  Technically, ground stations may be easier than the P3 
birds.  Of course mw bands present a challenge but not so much as one 
may think.

All the naysayers about mode-S found that the surplus equipment route 
actually worked out not too bad.  Not hugely difficult with the ample 
sharing of experience by fellow satellite operators.  Cost was not bad, either.

Anyway, there is room for both communities if there are satellites available.


73,
Ed - KL7UW
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