Re: satellite costs etc.

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Article #6931

#6931

From: Edward V. Wright
Date: Mon, 04 Jan 1993 19:16

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In <1993Jan1.165738.24729@ke4zv.uucp> gary@ke4zv.uucp (Gary Coffman) writes:

>Redundancy is always desirable if it's affordable, but there is a practical
>difficulty with having *cold* spares in orbit. Will they work when we need
>them? 

A cold spare is unlikely to be completely cold.  More likely it will
operated in a low-power mode so that you can still run diagnostics
and self-tests on the hardware.

>They have to be cold spares if they share the same orbital slot and
>frequencies. 

Not true.  You can put two birds in the same slot but only use
half the transponders on each one.  If the transponder frequency
X transponder fails on bird one, you switch to the frequency X
transponder on bird two.  If bird one fails entirely, bird two
can take over the entire service til a new backup is launched.

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<1992Dec14.221347.3359@iti.org> <1992Dec16.092029.27518@ke4zv.uucp> <1992Dec16.202219.2063@eng.umd.edu> <1gvlmnINN9c@mirror.digex.com> <72109@cup.portal.com> <BzMwDx.KGw@zoo.toronto.edu> <1992Dec23.111923.22269@ke4zv.uucp> <BzqBvs.J8H@zoo.toronto.edu> <19 <1993Jan1.165738.24729@ke4zv.uucp>

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Path: arc1-ca.pugleaf.net!sparky!uunet!paladin.american.edu!howland.reston.ans.net!usc!cs.utexas.edu!news.uta.edu!hermes.chpc.utexas.edu!news.utdallas.edu!convex!ewright
From: ewright@convex.com (Edward V. Wright)
Subject: Re: satellite costs etc.
Sender: usenet@news.eng.convex.com (news access account)
Message-ID: <ewright.726175018@convex.convex.com>
Date: Mon, 4 Jan 1993 19:16:58 GMT
References: <1992Dec14.221347.3359@iti.org> <1992Dec16.092029.27518@ke4zv.uucp> <1992Dec16.202219.2063@eng.umd.edu> <1gvlmnINN9c@mirror.digex.com> <72109@cup.portal.com> <BzMwDx.KGw@zoo.toronto.edu> <1992Dec23.111923.22269@ke4zv.uucp> <BzqBvs.J8H@zoo.toronto.edu> <19 <1993Jan1.165738.24729@ke4zv.uucp>
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