[amsat-bb] Re: Satellite user "communities"
kl7uw at acsalaska.net
Wed Dec 12 22:55:30 PST 2007
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
>Bob - AE6RV
I by simple you mean single-channel FM Leos and HF you mean linear
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
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
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
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.
Ed - KL7UW
BP40IQ 50-MHz - 10-GHz www.kl7uw.com
144-EME: FT-847, mgf-1801, 4x-xpol-20, 185w
DUBUS Magazine USA Rep dubususa at hotmail.com
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