Dave wrote:
On Mon, 19 Nov 2007 16:48:45 +0100, "Edgar" said:

Probably got its sense of direction screwed up by all the underwater sonar
noise that submarines etc. are making these days.

"These days" being the last 50 years?

You know that sonar has changed quite a bit over the past 50 years?
However even though transducer power has increased vastly thanks to
modern electronics, the amount that active sonar gets used is also much
less, again thanks to modern electronics and computational abilities.
Why send out a massive ping that can be detected 500 miles away when you
can quite nicely track a target 100 miles away using one ore more of
your passive arrays? Alternatively, again because the listening side of
the kit is so much better than 50 years ago, even if you have to go
active, an extremly low power ping will do, (something that couldn't be
done 50 years ago, you got a big ping, or no ping at all).

Cheers
Marty
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