There is a third figure of merit name for small receiving arrays that came
out of Syracuse University Research Corporation in 1967. It was
called SNIF for Signal to Noise Improvement Factor. A term apparently
coined by the author, Dr Martin Fournier. His report uses this term
to describe the SNIF based on directivity of electrically small multi-element
systems. Personally I kind of favor this term as it self describes the
improvement. However it is still subject to the downfalls of being based
on noise from all directions.
Lee K7TJR OR
>That's very true. Consider the K9AY. The RDF is about 7.7. Compare
that to a 1 wavelength Beverage which is about 7.9 dB. The K9AY has a
deep null in the 180 degree direction at the right elevation angle, but
45 degrees off that rear direction the signal is down only 10 dB. The
RDF number is a W8JI creation and serves its purpose, while the DMF is
an ON4UN creation and also has merit, but neither of these completely
encompasses all the things you may need to know about a receiving
antenna for your location. You have to use some common sense in
>junction with these numbers.
Jerry, K4SAV
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