"Jerry" wrote in
:

Could there be an arc going on inside the transducer as that is what
it sounds like?


You are listening to a pulse of supersonic sound you cannot hear that has
a peak power in the KILOWATT range. The click you hear is this godawful
power actually moving the bucket. You'll also hear it clicking if you
get near the transducer while the sonar is on. This is normal. It's
very powerful, that little crystal transducer.

You should see the transducers in the huge array that covers the bulb on
the bow of a submarine! Each transducer is about 5' long and the face
where the MEGAWATTS come out is about 8X8 inches of special rubber.
Hundreds of scanned transducers are in a special fluid behind a rubber
shield you see on the boats. Their transducers, normally, just LISTEN,
so as not to give away their position.

By the way, the sonar operators on the subs can hear your pinging a LONG
LONG way from you out in the ocean....(c; They have filters on 90 and
200 Khz and the other sonar ping frequencies used because the noise from
all of them can be deafening to the passive sonar.....

Speaking of the clicking, the AN/SQQ-14 (Squeaky Fourteen) Navy sonar has
a "click" that's so LOUD it will kill a diver in the water, and probably
whatever marine life has ears, too. Inside any ship nearby where it's
being used, everyone aboard has no trouble hearing the loud screeching it
does. Seeing the fish with that much power is no problem at all!....(c;


--
There's amazing intelligence in the Universe.
You can tell because none of them ever called Earth.