My trip home yesterday on the way to the airport, I got a very nasty surprise on my V1... An airport cop was parked perpendicular to the road with his K-band antenna facing in front of him. The cop seemed to be doing some sort of paperwork. Harmless right? I got about 3 secs of warning before meeting him, and probably the same amount after passing him before the signal disappeared.
Then, about 10 seconds later, my V1 went "DeDeDEEEEEEEEEEEEEEEEEE" showing a full-strength K-band bogey to the rear, and I could see strobing lights. My best guess was that the cop saw someone going fast and just rotated his antenna in line with the road.
Shows that even "harmless" orientations of radar could quickly turn into a threat in the blink of an eye.