> If I recall correctly, Mike and Jim have their own range,
> with the unit under test on one tower, and an HP spectrum
> analyser connected to a dipole on another tower, many
> wavelengths distant. Tower heights were on the order of
> 60'. A calibrated attenuator was used with the SA.
Well, the many wavelengths distant is already a problem.
Measurements would be much more accurate just out of the
near field. I don't know why anyone would measure an antenna
in the null of the pattern, and when a horizontal HF antenna
is at 60ft and the path is long there is a null along the
horizon! Bad measurement protocol.
Measurements would also be more accurate with a directional
antenna at the receiver also, and a good meter instead of a
spectrum analyzer.
Measurements like this are always a problem. Look at the
silly claims of the RAIbeam and that little two element hex
quad thingy. It's commonplace that measurements made in test
ranges that aren't really test ranges are a few dB off.
> Theoretically, the steppIR could be a bit better
> than a canonical yagi...in practice, it's hard to tell,
> because the differences are too small to matter.
Bingo....and probably too small to measure accurately also.
73 Tom
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