In my experience, you should never have to put the call farther than 30 to 50 yards at the most from you. Place it slighty upwind from your position is the best place possible.
First, you need to make as little movement as possible on each stand. This includes call placement. If your trotting your butt 400 yards out there to put a call down, chances are every coyote in the country is now heading out of there.
Second, if you place that call 400 yards out there, now what do you do if the coyote hangs up 400 more yards past your caller ?? Chances are your predator rifle ain't gonna make that 800 yard shot.
Last, after a day of trotting your butt off educating coyotes, your gonna go home mad and have no fur for the stretchers...
I own and use a FX5. Never have I had to place a call that far out for any reason what so ever.