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From: jeffj@sfmin.UUCP (J.S.Jonas)
Newsgroups: net.analog,net.misc
Subject: Re: "Nuclear Event Detector"
Message-ID: <634@sfmin.UUCP>
Date: Fri, 20-Dec-85 10:26:13 EST
Article-I.D.: sfmin.634
Posted: Fri Dec 20 10:26:13 1985
Date-Received: Sat, 21-Dec-85 05:35:31 EST
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Xref: watmath net.analog:573 net.misc:9019

> It is nothing much to look at -- a circuit in a multi-pin (round pin)
> package, and it is called the HSN-3000 High Speed Hybrid Nuclear Event
> Detector. The first brochure I got was titled "Certified Circumvention
> for Power Shutdown", and the second, largely similar, is titled,

	I can check with an army engineer if anyone really cares, but
when I got my brochure, I thought that it made sense.  If the radiation
isn't intense enough to melt the thing, or burn out the circuits with
induced EMF, it will simply cause the circuits to malfunction
during the irridiation period.  During this period of unreliable operation,
the data can be shoved into a 'safe' place, like a disk or shielded RAM.
When the levels are low enough, operation can resume.  It's sort of like
people going into a bomb shelter.  It works only if the bomb isn't
too big (in which case it doesn't matter) or too small (in which case
it isn't worth the effort since no damage will be sustained).
	Why no examples?  Maybe it's secret and/or confidential!
Or as my math teacher says "it's intuitively obvious!"!

	Radiation effecting circuit operation is not so uncommon.
The newer chips with finer details are very prone to malfunction
with beta or even alpha radiation.  I heard that the early DRAMS
(64k? 256k?) malfunctioned due to the radiation in the ceramic in
the packages.  The ceramic used today is substancially
less radioactive.  It never used to be a concern.

			Jeff 'it made sense at the time' Skot
			{ihnp4 | allegra | mcnc} attunix ! jeffj