"Ford Peterson" <ford@cmgate.com> writes:
"Late last winter, I was curious about the optimum length of a beverage.
I set out to decipher why the length was so important."
==========
IMO, a specific length for a Beverage antenna is not "optimum" unless it
is the length where the signal in the air and the signal in the wire are
90 degrees out of phase. This "optimum" length is about 2 wavelengths,
depending on the velocity factor in the wire. Beverage antenna gain
will decrease if one goes beyond this length.
However, going beyond this length will improve the antenna's F/B and F/S
ratios, perhaps improving its S/N ratio. I feel that Ford's tables would
be much more useful if they included the S/N ratio of the antenna as its
length increased. To do so, both the antenna gain and its pattern would
have to be taken into account.
The goal on the low bands is to have an antenna with a good receive S/N
ratio. That antenna is not necessarily the one with the most gain.
73, de Earl, K6SE
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