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Old September 29th 07, 02:51 AM posted to
[email protected] N2EY@AOL.COM is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 877
Default Suggestion for an HF starter rig

On Sep 27, 2:27?pm, AF6AY wrote:

If you are satisfied with your particular method of getting
RF out of the transmitter and into some antenna, fine.
Satisfaction is all part of the game. Such satisfaction is
not the example to set for all. It seems to me that every-
one's location is different and each presents a unique
problem to solve for the more-optimum EM wavefront
launch direction in that location.

Anyone who says that one kind of antenna is the "best"
or one should "always" use a certain kind of balanced
transmission line isn't looking at the whole picture. They
are probably describing just the only (or a few) antenna
installations they used. Yes, some antennas "work
better" than others. In a particular location.

All that is certainly true. But I don't see anyone
saying that one kind of antenna is "best" for all locations,
or that one should "always" use a certain kind of transmission
line in all applications.

It's also not the whole story, either, because what
must also be considered is the sort of radio operation
that is being considered. Does the ham want only DX,
or regional/national QSOs? Several bands, or only one
or two? Will operation be confined to one part of a band,
or spread out over the entire band?
What time of day will most operating take place?
Will there be ragchewing, net operations, contesting?

All that and more have an effect on what the 'best'
antenna is for a given location.

For someone just starting out, I would suggest just a
vertical for HF.

Depending on a whole bunch of factors, that could be
good advice, or very bad advice.

It is the least obtrusive to neighbors

Not always. It depends on the location. A wire
antenna can be much less noticeable than an
HF vertical in many situations.

be described as a "flagpole")

Perhaps, but I don't think anyone who has
seen a typical manufactured amateur HF
trap vertical would consider "flagpole" an
accurate description.

and most will perform
adequately (to launch an EM wavefront) with a few radials
for the "ground."

Maybe - and maybe not.

The performance of an HF vertical is dependent on
many factors, such as the ground system, objects
in the near field, how much loading is used to obtain
resonance, ground losses in the Fresnel zone, etc.

No, it won't win awards or work DX
"better" than Brand Y using Brand T transmission line,
but it WILL radiate adquately...and that's the whole name
of the game, ain't it? :-)

It may not radiate adequately.

For example, on the lower HF bands such as 80/75 and 40 meters,
the dimensions of a full-size quarter-wave vertical and radials may
become impractical (60+ feet on 80/75, 30+ feet on 40 meters).
Most trap vertical designs use a considerable amount of
inductive loading on those bands, reducing the efficiency and
radiation resistance as well as the SWR bandwidth.

The lack of high-angle radiation from such a vertical may make it
almost useless for daytime and closer-than-DX-but-farther-than-local
communication on those bands. An amateur located in a valley, such as
the one who started this thread, might prefer
useful radiation that leaves the antenna at angles that would leave
the valley.

At this point in the sunspot cycle, the amateur bands above 11 MHz are
often useless for ionospheric propagation much of the time,
particularly during darkness hours. Having an effective antenna for
the lower HF bands can be the difference between making QSOs
and not making them.

There's also the cost factor.

Yes, "everyone's location is different and each presents a unique
problem to solve". Which means that recommending a vertical
antenna to someone just starting out could be very bad advice unless a
lot more information was gathered first.

And if Brand Y using Brand T transmission line works better,
why not use it?

IMHO, the "whole name of the game" is useful radio
communication. IOW, making QSOs.

I have seen situations where it was good advice to tell a ham starting
out on HF to put up a vertical. I have also seen situations where that
would be very bad advice. Same for dipoles of various kinds,
loops, random wires, etc.

73 de Jim, N2EY