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- January 8, 2018 at 6:05 pm #11538
Below is a graphic using MoM software to study the effects of installing a vertical monopole close to another physical structure, such as a wood-framed house.
The closest wire conductors used to construct the framework shown in the graphic are located six feet away from the vertical radiator. Those wires would behave (roughly) like the interior a-c power lines of a typical frame home. The far-field radiation patterns are shown for this layout, for a frequency of 7.25 MHz.
The patterns for the MW broadcast band would be less affected, due to the longer wavelengths in use.
January 8, 2018 at 7:02 pm #56379RichPowers
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Total posts : 45366Your chart says it’s a 33 foot antenna 6 foot from a re-radiating structure, shouldn’t it be a 10ft antenna by a wood house?
January 8, 2018 at 7:38 pm #56380Carl Blare
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Total posts : 45366What does 7.25 MHz have to do with our low power hobbY?
January 8, 2018 at 8:43 pm #56383Rich
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Total posts : 45366… with 18 ohm R-F resistance in base loading coil, and base of the 3-m vertical monopole located within 6″ of the earth.
The nearby structure produces little adverse effects to the shape and gain of the radiation patterns of the monopole, for these conditions.
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January 8, 2018 at 9:30 pm #56384wdcx
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Total posts : 45366low power hobbY
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