in further on distance to horizon...

Consult various editions of Engineering Handbook as published by the Natiuonal Association of Broadcasters..

It has proven verey realistic for remote broadcasting for our station...In fact we broadcast a number oif football games from Port Lavaca some 28 miles from out studio
with
transmitting antenna 75 feet above ground -- 30 feet above sea level ground level
receiving antenna 75 feet above ground -- 100 feet above sea level ground level

distance (miles) 1.41 times square root 75 feet of transmitting antenna plus 175 feet of receiving antenna
1.41 x (8.66 + 13.22)
1.41 x 21.88 = 30.86 miles

Hope this helps you Joe Tibiletti