Antenna question...On a chase truck (crew cab) a permanently mounted roof antenna in the center of the roof is ideal correct? I am wondering what the difficulties would be with the addition of a bed rack?
If there is a bed rack that extends over the cab with stretch metal across it what would be the best mounting situation?
What would be the case with a bedrack that only extends over the back half the cab roof ?[/QUOTE
Half rack, your most effective (probably only) transmission would be to the front of the vehicle.
The key to effective antenna is ground plane. It needs at least 9" around the antenna base to operate "as advertised".
I you put ANYTHING in the path of the radio waves, it will block transmissions in that direction. That includes tire and what have you above the level of the cab on a rack in the bed. You can build an antenna mount on your chase rack, just dont forget to allow for ground plane.