[Towertalk] Terrain Analysis

[mwdink@eskimo.com]

What I learned last week has taken me to a new
area in my Amateur career. Terrain Analysis.
Fascinating stuff.

For those who have played with the Terrain analysis
programs - some questions. 

I have been developing elevation files for my QTH. 
The sample elevations files in YTAD/YT seem quite 
large in their distance intervals (100-200 feet). 
This may because of the use of regular topographical 
maps. Using DEM (Digital Elevation Map) files, I can 
get my intervals down to .01Km (33 feet) and go up 
from there. In fact, I use .01Km for the first .5Km,
.05Km intervals to 1Km, and then .1Km intervals
to 5Km which is where I stop. 

Am I working too hard at this? (I guess I could change the 
data to bigger steps and see if the graphs change.) My terrain
has a lot of variation and I figured I couldn't be too 
detailed but does YT/YTAD really make use of that kind 
of detail? Does a range of intervals like I have selected
mess up the calculations - should I stay fairly consistant 
instead? 

So, far, what I see is very interesting - higher is definitely
not always better if these graphs have any validity :>)  which
is my question. For those who have used it these programs, do the
results bear out? (Before I start thinking about moving
antennas. <g>)

Neat to learn new things. Gives me an appreciation of the
complexities involved in signal arrival.


73
dink