Dr.Greg has presented on the Forum the Lorentz-Einstein transformations (LET) expressed as a function of k=[(1+v/c)/(1-v/c)]1/2. The important fact is that the LET are clock synchronization independent. Because special relativity is a very flexible chapter of physics, I have tried to express the LET as a function of the time at which the radar signal is emitted. Let e' be that time and t' the time at which it arrives at the location of the detected event, the detection taking place in the I' inertial reference frame. Let x' be the space coordinate of that event. We have x'=c(t'-e') (1) t'=(x'/c)+e' (2) Equations (1) and (2) enable us to express the space-time coordinates of the detected event in I as a function of e' x=kx'+[tex]\gamma[/tex]Ve' (3) t=[tex]\gamma[/tex][t'+(v/c)(t'-e')=kt'-[tex]\gamma[/tex](V/c)e' (4) In the case of the "everyday clock synchronization" which is equivalent with the synchronization performed with a signal that propagates with infinite speed t'=e' (3) remains unchanged. (4) becomes t=[tex]\gammat'[/tex] Do you find some flow in the derivations above. What is the way to Selleri?