Some of the more aerodynamic styles have a fiberglass or plastic radome which covers the actual antenna that are 3-5" long, maybe 3" high and only about a half inch thick. SUVs and vehicles with larger roofs for more ground plane work well with these. :wink: 73, n9zas
Spoke with someone who said that is a GPS antenna tied to the $1,700 MDT. It allows dispatch to track the Trooper's location and gives the Trooper's accurate info on his and other's current location for MV stops, calls in progress, etc.