> I have had success in the past with 300- to 350-foot beverages. I started
> with a 390-ohm termination, but did not get good f/b until I paralleled
> another 390 ohms with it to get under 200 ohms. One of them worked best
> with the far end connected directly to the ground rod -- a termination
> equal to conductor and ground losses.
In addition to what Gary said, you can add loading inductors
periodically along the antenna. The Zo of the antenna increases
(requiring a termination higher than 1000 ohms generally) and the
pattern is very similar to a much longer Beverage.
The loads need to be every 1/8 wl or less, and the value adjusted
so Vp is .5 freespace with a 1/2 wl wire. You could do that on a
modeling program.
This method gives the best pattern in a short antenna. If you use
too much inductance, the pattern reverses and isn't as good.
73, Tom W8JI
w8ji@contesting.com
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