Re: "white noise" monitoring?

From: Chris L Peterson (clp_at_alumni.caltech.edu)
Date: 01/22/05 

Date: Sat, 22 Jan 2005 20:36:11 GMT

On Sat, 22 Jan 2005 13:01:21 -0700, Tim Killian <TJK@notmyrealemail.com>
wrote:

>Spread spectrum signals can be broadcast at extremely low levels and
>they don't alter the spectrum enough to be detectable without tremendous
>effort. A receiver with the proper chipping sequence can extract the
>signals from what appears to be random noise.

Yes, but I think what is being discussed is _people_ directly hearing or
seeing messages in noise. That's quite different from a spread spectrum
receiver doing it (and as you say, it just appears to be noise in that
case... it isn't really.)

>On the subject of anomalous detection, how do you suppose all of those
>wild animals detected the imminent tsunami danger last month?

I have seen no convincing evidence at all that any animals detected the
tsunami. In fact, I've seen no convincing evidence that animals ever
routinely sense seismic activity, at least not more than a few seconds
earlier than people. I remember a couple of occasions when living in
California where the cat got spooked before a big earthquake- maybe five
seconds before I first heart them. Nothing too mysterious there.
Certainly, in the areas affected by the recent tsunami, massive numbers
of dead animals are contributing to the disease problem.

_________________________________________________

Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

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