a true range check to check new radio and plane installion should be severall hundred yards with antennae extended fully.usually one person holds the plane other person starts walking till plane barely visible and moves controls in pre arrange sequence.any jittery servos or loss of signal ,do not fly till problem fixed or radio checked out.this method though time consuming also test the antennae which could have a bad connection between the joints from dirt/grit.after this initial test is passed you can do the quick check with antennae down see what the range is and then before every flying session you can check range and if any difference is noted do not fly till problem of reduced range is found.