Since terrain effects have entered the discussion, here's my 2 cents (probably less) on the subject. Like any modeling program, be careful interpreting HFTA results. See my earlier post at: http://li
Thanks Shawn. Yes, Dean told me the same things., but he also advised me to run a lot of simulations to find those that didn't have that spatial aliasing. BTW -- the terrain data is a plain text fi
A pair of numbers on each line ... distance,height One line per point ... The distance values need not be evenly spaced but they do need to be "in order" (increasing). 73, ... Joe, W4TV On 2019-01-19
Excellent post Shawn. I was concerned about this when W9AC mentioned small height changes making big radiation angle differences at W3CRA(sk) http://lists.contesting.com/pipermail/towertalk/2019-Janu
The HFTA terrain file is a simple ordered list, and as you say it can be edited with any text editor. Each line in the text file represents a different data point ... the first number is the range,
I was concerned about this when W9AC mentioned small height changes making big radiation angle differences at W3CRA(sk) http://lists.contesting.com/pipermail/towertalk/2019-January/162525.html Also I
another mountain range about 15 miles east of me and by editing the terrain file to either include it or not I can see definite differences." And that brings me to this point: consider a case where
"Certainly the topography of adjacent radials affects the true performance on one radial that won't show up in the HFTA model. No?" I'm pretty certain that N6BV himself has pointed that out as a limi
I'm pretty certain that N6BV himself has pointed that out as a limitation of HFTA. It's a complicated world. HFTA assumes that (for each direction) the profile is infinite in extent in the "cross ra
Thank you, Shawn, for this excellent posting. 15 years ago, while my house was being constructed here in New Mexico, I observed the same effects while trying to determine optimal heights and locatio