Originally Posted by boojay
thanks for the vid. so is it measuring the speed of your serve as it crosses the net? if that's the case, then your serve would be faster since pro serves are measure right after contact, if i'm not mistaken. Or is it reading your serve as the ball is coming toward the radar? In any case, your true service speed would be faster than those readings.
It takes the reading as it crosses a certain plain/bubble in front of the radar gun. So, it has to come into a ceratin area for the serve to be clocked. I guess the answer to your question is it does not measure it immediately after contact, rather as it approaches a "that area" in front of the gun.