Bill, K0HA wrote:
> Why is there so much concern on Beverages and Yagis on front-to-back
>ratio? I always design my Beverages and Yagis to have a small back
>lobe with two nulls on either side of it to increase the size of the
>null area...
====================
Hi Bill,
I don't know if there is any concern about F/B ratio for Beverages, but
IMHO, I feel the reason the Beverage is such a good receiving antenna is
that it's so quiet (it's certainly not because of it's negative gain!).
And it's quiet merely because it's directional (not that it's
horizontally polarized, which is untrue -- it responds mostly to vertical
polarization).
I included the 5-degree elevation angle values because I assume that some
are interested in decreasing local man-made noise levels coming from a
specific direction.
The termination resistor value in the models which results in best F/B
also happens to result in max forward gain and lowest reception angle,
both of which are good indicators of best directivity, therefore lowest
noise, no?
Years ago, when I walked one of my Beverages with an FS meter to find the
best termination value and came up with 300 ohms, and now, when finding
in the models that 300-350 ohms is best for a Beverage over "very poor"
soil gives me a clue to the soil conductivity here in the Mojave Desert,
hi.
73, de Earl, K6SE
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