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Old June 18th 08, 05:49 PM posted to rec.radio.amateur.moderated
Michael Coslo Michael Coslo is offline
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First recorded activity by RadioBanter: Jun 2006
Posts: 828
Default Antennas - Is NVIS a good thing?

Jeffrey D Angus wrote:
Dick Grady AC7EL wrote:

However, the object of Field Day is to contact as many
stations as possible.


I thought the purpose of Field Day was to serve as a training
ground for emergency preparedness. And a time to experiment
with new techniques and technology in an "emergency" setting
without it being a "real" emergency.


I think you are both correct. While the purpose is emergency
preparedness, the format seems rather contest like. Keeping score,
different classes, posting the scores in QST. It's just a way to inject
some fun in the whole process. Get folks on the air, and nothing like a
little competition to get a person to improve their skills.


Considering the relative ease of setting up an NVIS antenna
system, and the number of other stations on the air, Field
Day makes a perfect time to see how it performs and to map
it's effectiveness for short range HF communications.


Let's look at Field day. We're pretty much not DX'ing to begin with.
Excepting Alaska and Hawaii, the distances aren't that vast.

So a Low takeoff angle antenna isn't even the best choice, IMO. My
experiments show the low angle antenna to have a very strong local
signal, then for a few hundred miles out it is not very good, then it
starts improving, and for very long distances it tends to be better than
the NVIS type.

That was done on 75 meters, and keep in mind that it was not over a long
period of time - around 2 weeks, but I'm fairly confident that I'm at
least in the ball park.

I worked Field Day once overnight on 75 meters using 100 watts, and an
off center fed dipole at 40 feet. I used that setup to work the west
coast, and Hawaii and Alaska. I ran and held frequencies the whole night
long.

I would recommend if a group was going to put up a "DX angle" antenna,
they would be well served to put up an NVIS antenna to complement it.


Maybe I'm going blind in my old age, but I just don't see
contesting under 47CFR97.1


Ever since cavemen started rolling boulders around in the woods, they
figured out how to turn it into a competition. It seems to be what we
humans do best. ;^)


- 73 de Mike N3LI -