> > The absolute signal levels in dBm that are published in the comparison
> > report are consistent with pattern look angles that are significantly
> > attenuated relative to expected boresight gain. In my mind, any
> > suggestion, implied or otherwise, that boresight performance of the
> > antennas under test can be extrapolated from field strength measurement
> > made deep inside a pattern null is dubious.
I would agree if one attempted to do this on a single antenna. But this is a
COMPARISON, and all are equally subject to the same attenuations. It is
remarkable is it not, that they all really came up with relatively equal
gains, save one? And where modelling is available, the gains specified are a
bit shy of predicted.
> >This is not to say that the
> > tests weren't carried out with great diligence and care. I believe they
> > were. I am only concerned about the strength of the link between the
test
> > data and actual skywave performance.
>
> Well put Mike.
>
> Measuring in a null, no matter WHY it is there, is always a bad
> idea (unless that is the point of the pattern you are interested in
> using to communicate).
> 73, Tom W8JI
> w8ji@contesting.com
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