I apologize :( , if i was unclear in the post.
if i understood , the distance for a 860 mhz will be
(3X10e8/8.610e8)(0.84)= 0.2930 mts (where 0.84 is the
factor for a Heliax 1/4", if i need more distance it will be
(0.2930)(2) or (0.2930)(3)...etc.
what others factors i must consider.
Thanks for ...