[Rich]

My point about the radar, was not to be standing on the non-moving ground while taking the reading, of course that would provide the same speed as the GPS.

The problem would be to be on a platform (such as a boat) that was moving with the current. Of course, that speed would be variable, due to the influences of many different factors.

But as always, this is always confusing and will always be debated to the n-degree!

But if anyone would like to play with my radar gun, let me know.