just math!!!
1.25x (square root distance agl...in feet)
AGL= distance above transmitter.
Answer= xxxx n.m.
I think!!!!!!!!
Therefore... 5000 ft AGL equals signal reliability of 88.39 n.m. Sounds about right!
Anyone else please correct/add input if I'm wrong!
D.K.
P.S. DME is another story!!!