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Re: P3D information

on 10/6/00 4:15 PM, Phil Karn at karn@qualcomm.com wrote:

> We just have to let go of analog modulation and the lower frequency
> bands.
> Just as DirecTV didn't worry about backward compatibility with 3m
> C-band dishes, neither should we worry about backward compatibility
> with existing mode B stations.

If this isn't the biggest bunch of rot I've heard!  Sheesh.

Let go of analog?  Oh, that's right.  You're a "digital only" guy.  And
being that you work for Qualcomm, it suits your company's philosophy to be
rid of analog.

Oh well..I won't let it go.  I LIKE ANALOG!

Secondly, yeah, DSS dishes are small.  But they are DISHES and at 12 GHz,
there is a LOT of gain in those things.  They are VERY directional antennas
which means they have a LOT of gain.  If you are off a couple degrees with
them you lose signal.  You can pack more oomph with a small microwave
station simply because your wavelengths are smaller and therefore geometries
of resonant structures are smaller.

But it's harder to generate power up there and more expensive.  Most guys
have mode B and mode J capable stations and that is what is most readily
available.  I hope that the control ops of P3D wouldn't be so foolish as to
rarely use those modes which means that many people have to go and buy new
equipment which they cannot necessarily build or afford.


Jon Ogden
NA9D (ex: KE9NA)



"A life lived in fear is a life half lived."

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