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From: dep@ius3.ius.cs.cmu.edu (David Pugh)
Newsgroups: sci.military
Subject: Re: Siganl Flags
Keywords: lasers?
Message-ID: <10141@cbnews.ATT.COM>
Date: 12 Oct 89 03:18:46 GMT
References: <9869@cbnews.ATT.COM> <10104@cbnews.ATT.COM>
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From: dep@ius3.ius.cs.cmu.edu (David Pugh)

In article <10104@cbnews.ATT.COM> jwm@stda.jhuapl.edu (Jim Meritt) writes:
>The Navy (NATO, anyway) uses signal flags for tactical signals. ...
>It is the ONLY way at sea under radio silence - messengers don't swim
>that fast.    :-)
>[mod.note:  Surely we haven't forgotten how to use signal beacons ? -
>Bill ]

Or how about a low-power laser? If the entire "footprint" of the laser falls
within the target (which should be easy enough to do: use a laser with a
small divergence and adjust the aim whenever it drifts too near the edge
of the target), the signal should be undetectable.

For that matter, why doesn't the army get into the act...I'm sure they could
find a use for a secure & undetectable LOS communications system.
-- 
... He was determined to discover the		David Pugh
underlying logic behind the universe.		...!seismo!cmucspt!ius3!dep
    Which was going to be hard, because
there wasn't one.	_Mort_,  Terry Pratchett