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RE: P3D information



> Who knows.  The first year will be mainly putting the 
> satellite into orbit.
> Mode B will probably be the only thing available, but at low power and
> sporadic times at best.

Highly likely.  Without the gain antennas active, and in the early days,
without the availability of suitable digital hardware, Mode B is probably
the most practical mode to fire up.

> Perhaps. But there are a lot about the microwave bands that 
> we do not know
> yet since we've never had a bird with greater than an S band 
> downlink.  What
> will doppler shift or antenna pointing be like on 10 GHz?  
> Will we have rain

We can do a few calculations on the basic parameters.  Doppler shift can be
calculated using sample keps, which have been distributed, and antenna
pointing issues can be worked out, based on the gain of various antennas,
beamwidths and other pattern issues.

> scatter problems, etc, etc.  All cool and fun stuff to find 
> out, but these
> bands are a question as to their "ease."  There is also the 
> cost.  Not only
> do you have to buy the "IF rig" but all the transverters as well.
> Microwaves are much more costly.

That's if you use an existing rig at all, in the case of digital.  It is
likely that digital transceivers will be a whole new device.  
 
> Also, if DSS and small dishes are so good, then why aren't TV 
> networks and
> broadcast stations flocking to use them?  Because they aren't good
> enough....

Also the issue of consumer quality versus studio quality...  And in the case
of voice, do hams really need "toll quality" speech?  Obviously not,
otherwise we'd have dumped SSB years ago! ;-)
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