[Rob]

Brian,

I guess you are right.

That reminded me of an interesting observation I made once. While fidgeting with my keys at the back door of the house at night in the summer while many moths were buzzing around the lights by the door I observed that at the sound of the keys the moths would all take off and disappear. The only thing I can figger' is that the moths must be reacting to the ultrasonic sound and in thinking it was bat 'sonar' were exiting the scene as to not become dinner.

Rob