function graphpoldiff(dkl,mylon,mylat)
% graphpoldiff(dkl,mylon,mylat)
% Figures with polarization shifts in EME-contacts with 
% 12 different locations. The polarization is plottet in 
% dependence of the time in hours relative to the moons 
% culmination.
% blue line:  both antennas are horizontally polarized
% red line:   my antenna is polarized parallel to the 
%             earth axis while the other is horizontally 
% Parallax is not taken into account (moon at infinity). 
%
% dkl   :  declination of the moon in degrees
% mylon :  geographic longitude in degrees ( west is positive)
% mylat :  geographic latitude in degrees  (south is negative)
