Richard Clark wrote:

Hi Stefan,

You seem to be simultaneously agreeing and disagreeing. The hill is
either in the way, or it is not. It is in the way. To count on an
intermediary, such as suggested by Jimmie, knife-edge propagation or
bend of the waves, is probably not in our student's syllabus. Besides,
I have seen neither you nor Jimmie offer the attenuation presented by
such refractions (and the attenuation is not marginal). Without
quantifiables, the path budget cannot be calculated.

The problem, as stated, has a clear answer in looking over the hill by
raising one antenna, the question informs us that is the answer and
that is simply resolved with trig (albeit, including the radius of
earth and accounting for its curvature).

73's
Richard Clark, KB7QHC

Might I recommend a program misleadlingly called Radio Mobile. This
piece of software will all let you check many real world situations.
This program is not real easy to use, it's a lot worse than Windows or
Office (ok, not worse than Office), but it is worth learning unlike the
previous 2 mentioned.

The site you need for the software is

http://www.cplus.org/rmw/english1.html

and then you need to download a large amount of terrain data, which is
freely available from NASA. It looks like the way this is handled has
changed since I did it last, so I can't comment on how it is done now.

tom
K0TAR

On Wed, 07 Feb 2007 22:24:26 -0600, Tom Ring
wrote:

The site you need for the software is

http://www.cplus.org/rmw/english1.html

and then you need to download a large amount of terrain data, which is
freely available from NASA. It looks like the way this is handled has
changed since I did it last, so I can't comment on how it is done now.

Hi tom,

I was involved in Beta testing this. The current version allows
dynamic map loading over the Internet, and overlays of Mapquest, Tiger
or many other mapping programs available. I've been using it heavily
for the last few months and its world of variables allows for finely
grained analysis. However, it also allows for massive headaches if
all you are looking for is a simple solution. In short, no
quantifiables are going to follow from your recommendation - unless I
do it. This lil Red Hen isn't interested in cooking that bread.

73's
Richard Clark, KB7QHC