In a message dated 5/21/03 4:28:26 AM Eastern Daylight Time, jimsmith@shaw.ca
writes:
>
> Is there an affordable program which will combine propagation
> predictions and antenna characteristics and tell me, for any path of my
> choice on any HF band, the likelihood of making Qs on that path?
There are some, but..
trying to "program" or forecast propagation is like trying to predict
weather. We just had last week prediction of gloomy rainy wx for weekend, but
were blessed with fine sunny days. This is taken care of by sophisticated
computers and WX departments.
Propagation problem is worse in respect that you have involvement of
atmospheric conditions, height of the layers, daily variations, solar flux,
storms and anomalies. Rough prediction we can do, just like with weather - if
it is cloudy, it mostly likely would/could rain. With propagation we expect
certain patterns depending on frequencies and directions. Then there is whole
ball game depending on station equipment/antennas/location.
I think practical contester's approach is to get the rough feeling what to
expect, choose the category/band to operate and go full bore, have fun and
see what happens. I used to do detailed analysis of my previous years'
operation, competition, figured out how many Q and mults I need to make to
beat the record. Then contest starts, solar flare arrives and messes up the
whole strategy. First hour I would make 5 QSOs instead of 200 and rest of the
contest was operation of frustration. I learned to get ready the best I can,
and just go in and have fun, send the log and sometimes new record or a
trophy would pop up, making me feel good. It is like a lottery to certain
extent, you got to be there, play, in order to win (sometimes).
There are software packages that allow to show coverage of popular directions
and angles and then comparing the angles of your antennas (seen them
demonstrated, forgot the names, never used them). Terrain has a lot to say to
formation of antenna pattern, low sunspot activity depresses the atmosphere
height and propagation angles. It is quite complicated, but this unknown is
what makes it attractive and fun. I try to have the best antenna system
capable of taking advantage of various conditions and be there when it
happens ("you never have enough antennas"). You win contests by working
stations that others can't and that comes from experience and antenna arrays
(given top operator and equipment).
To have software that would predict openings and probability of QSOs for
given antennas would be nice, but most likely it would be "accurate" formula
with fuzzy variables. Better than nothing, but hardly accurate or winning.
Personally I want to be heard (almost) everywhere, under all angles and be
able to dig out weak ones with best S/N discriminating (steerable) antennas.
That's what I am working on. Antenna modeling helps to design antennas, and
when propagation happens, I want to be able to take advantage of it and have
fun.
I don't believe computer program can beat experienced operator, but it can
only help especially the new, growing contesters. So good luck and don't
forget long path, skewed path, gray line, reflections, refractions, ducting,
backscatter and other modes of propagation. Keep us posted.
73 Yuri, K3BU, VE3BMV
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