Hey there Richard, yes that is what I thought about these sensors but then I notice if I put my hand in front of it, I will see the red dot showing my hand on the windows graphic radar at one side of the animated sweeping Window. That confused me as it looks like the sonar is actually moving left and right when I know it is not really moving at all. How does the animation seem to work? If I put hand on right side of sensor, the red blip also will show on the right side of screen after the animated sonar beam moves to the right. Of course I know the sonar beam would be so much wider if I had a servo moving the sensor but it still seems to have the illusion of moving on the windows sonar animation. This is why I use 2 sensors front left and right and they both seem to show accurately where my hand is making a red ping dot ,even with no servos moving them....I know I always have trouble explaining things clearly but hope you see what I mean,LoL! Edit......

Actually Just watched carefully the beam animation really is just nothing as I do notice the red dot will show all the way across the screen, not just one side.I think I understand it now,sorry guys, my mistake I should have watched more closely before.Like they say...learn something new everyday!