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Re: AMSAT has a SECRET!



Bob:

First nice to meet you.

> Here is my take.  I want to build a 2m uplink, 10m downlink linear
> satellite.  Yes, Its the old MODE-A,  BUT design it for HT'S!

Well if were are into a sync. transfer orbit the 10M downlink will get lost
as the bird heads out for apogee.  I have just recently had a chance to look
at the innerds of some of the newest dual mode, satellite and cellular,
units and the silicon would be vastly happier at 435/2401 than it would be
at 144/28.  I am an old fart and I dont go for the letter designations, the
frequencies are so very simple hi.

> We will have what Irridium and Teledesic, and Globalstar all promised but
> never delivered.

Isn't it interesting!  I noticed, being from the telephone industry, that
those LEO proposalls did not seem to notice that 70% of the world is covered
in water and even I could see there were not many whales and sea lions that
were on the lists of those who were looking for telephone service.  It was
not popular back then, early 90's, to mention that 70% of the time the
satellite investments were over water and thus in a 99% non revenue earning
position.  I guess the whales didnt want to phone Green Peace after all hi.

> Cheap HAND-HELD satellite communications from anywhere.
> All we need to do to the Mode-A is beef up the downlink power so that an
> HT with a rubber duck (Innefficient 10m receive antenna) can still get the
> downlink.

Well this is doable IF AMSAT had satellites that were consistent and
reliable the manufacturers would rise to the opportunity.   What we need is
to keep the complexity on the ground (such as digital modulation schema etc)
and make the satellite as simple as possible.  Dr. W. Edwards Deming taught
us a great deal about how to build reliable systems didn't he?

On the other point, if someone plays in highway traffic they often wind up
as road kill hi.

Larry
VA3LK



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