No. You'd be missing the essential point which has to do with the "shape"
of the tool and whether it was remotely suited to the problem.
The best estimate of NEC applied to this problem, even with a cage for the
building, will likely be buried in inescapable inaccuracies. The
cage's good point is that at least it is not based on a
doomed misconception of how the NEC code works.
IF the building is all metal construction, the cage may return some halfway
decent description of RF behavior. If it's concrete over rebar posts with
indeterminate connections to the facing, the outcome is probably unknowable
in advance of antenna installation. And it's important to understand that
the model is NOT useful in this case, rendering all-issue (e.g. noise,
interference) anecdotal advice from those who have attempted the same the
better counsel.
73, Guy K2AV
On Tuesday, August 11, 2015, Jim Brown <jim@audiosystemsgroup.com> wrote:
> Ah, perfection. Sadly, EZNEC does not provide that set of options. If I
> could build that model, I would. But I can't. I will take this first
> approximation, understanding its limitations. Brown's 99th law -- never
> let perfect be the enemy of good. We don't know the nature of that roof,
> so modeling several possibilities and using the result to TRY things seems
> like a pretty good approach to me.
>
> 73, Jim K9YC
>
> On Tue,8/11/2015 12:42 AM, Guy Olinger K2AV wrote:
>
>> In order to estimate your hypothesis you need to create a building shaped
>> cage of dielectric wrapped, resistively loaded, interconnected wires. It is
>> necessary to bookkeep in the model that the roof, as conductor, is
>> connected to a vertical conducting face on four sides and then to ground.
>>
>> These faces electrically are at least in the quarter to half wavelength
>> range vertically and can radically effect the appearance of the roof as
>> conductor. These faces can have significant radiation. These faces can be
>> the majority radiator with the dipole serving mainly as a matching device
>> to the building as majority radiator.
>>
>
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