In a message dated 5/10/00 1:34:50 AM Central Daylight Time, [log in to unmask]
writes:

<< The interesting thing is that I have yet to read of a real test done on
them
 by anyone except a believer or a manufacturer.  >>

Anecdotal... since we installed sonic devices in our shop the incidence of
the lower echelons, myself included, getting woken at 2 AM by a phone call
from the alarm company because a mouse or squirrel is running around in the
shop setting off the alarm, awakening the entire neighborhood, has been
noticeably reduced.

I'm not sure it has any deterrence effect on thieves.

I've been using for years a sonic device that is supposed to mimic a
dragonfly to keep skeeters away. You wear it around the neck. Not sure how
well it really works. A close second to the battery vibrating "massage"
goggles. Both are good for starting conversations at parties.

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