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Old December 28th 08, 03:06 AM posted to rec.radio.shortwave,rec.radio.amateur.antenna
John Smith John Smith is offline
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First recorded activity by RadioBanter: Nov 2006
Posts: 2,915
Default Shortwave Radio Listener (SWL) Antennas -versus- Amateur RadioAntennas

Dave wrote:
John Smith wrote:
RHF wrote:

...
js - but alas i remain a simple shortwave listener
who simply enjoys listening to the radio; cause
practically speaking; that is what i do
- - - respectfully ~ RHF
.


Quit peeing on my leg ...

Brother, I enjoy having a good time, a good drink and the company of a
good woman as well as anyone; And, furthermore, I am here because I
enjoy a good antenna as well as anyone else.

I am here because some know much more than me, can explain it in a
manner which I can absorb (Cecil is but one example), and I expect
there is much more for us ALL to learn, indeed ...

I ain't here to lecture you ... I ain't here to be a ham ... I ain't
here to play the game of "one-up-man-ship"; I am here to catch what I
missed "the-first-time-around"--end-of-story.

But now, a good argument, a good debate, a good "theory-session" ...
count me in!

Sit back, and pick on the next guy in line ... ;-)

Regards,
JS


A random wire (e.g. inverted L) transmits nicely if you use a tuner at
the feed point.


A resonate 1/4 wave dipole transmits "nicely" and uses no lossy tuner
.... a resonate 1/4 wave vertical monopole, with drooping ground plane,
transmits "nicely", requires no lossy tuner, and is damn near a perfect
match to 50 ohm coax ...

A 1/2 wave version of either of the above produces a superior pattern
and can be matched with either a T-match or gamma-match ... indeed, a
very minimal counterpoise is all which is necessary--and, if things are
"perfect", not even that is needed, or simply a choke on they outside of
the coax a ~1/4 wave away from feed point. A 5/8 is non-resonate
physical length, and even demonstrates a superior pattern (at least on
paper and with antenna prediction software ... )

However, in side-by-side comparisons on 10-6-2m antennas I have built,
comparing a 5/8 against the 1/2 (construction methods/materials and
matching components identical) ... the actual difference, in the real
world, must be less than the width of a meter needle in the readings ...
or, put simply, I no longer deal with the extra length required of the
5/8 ... your mileage may vary ...

Regards,
JS