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Author Topic: Reflector or ground plane?  (Read 734 times)
W1JKA
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Posts: 1808




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« on: March 25, 2012, 08:57:05 AM »

   First off I'm a qrp/cw operator and avid seat of the pants antenna experimenter (no EZNEC for me),also a retread ham 43 years qrt.Three years ago I homebrewed a new Carolina windom (66 ft./ up 25 ft.) which worked very well for me into Europe and w.coast USA.I then put a 12 ft.(24 ft.) aluminum extension ladder on the ground under and parallel to the radiators centered under the  vertical 10 ft. Q section and overall my rst reports and dx has improved with this set up.I then put the ladder on top of 5 gal. plastic pails to isolate it from the ground and had the same results.This is not a one time propagation freak as I have A/B this during different seasons,nite/day,during qso,s over a three year period.I'm sure I am not the first person to try this and am curious as to why the ladder causes the same results when in my limited view, the one on the ground its a ground plane and when on the pails it is a reflector or are they both one of the same ?
Thanks for any insight.  Jim                 
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K0ZN
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Posts: 1560




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« Reply #1 on: March 25, 2012, 10:03:38 AM »


 Wild guess.... and not to be flippant: the sunspots have also improved in that period of time as we move towards the cycle peak. Almost every station seems
to be getting out better as we approach the top of the sunspot cycle. (What separates the men from the boys is how well you do at the Bottom of the sunspot cycle !)

 Electrically, it is a pretty hard thing to figure unless someone does some extensive modeling.  A wild guess:  *possibly*  (I am not going to
speculate how) it improved the match or reduced ground losses in some way.  That said, it has always been my impression that a good ground system does seem
to benefit most antennas. Although theory does not confirm that with most horizontal antennas. It will be interesting to see what other opinions and guesses you get on this.

73,  K0ZN
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WX7G
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Posts: 6197




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« Reply #2 on: March 25, 2012, 10:13:55 AM »

I ran a NEC-2 simulation of the antenna with and without the ladder. There is NO difference in the radiation pattern.
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