Rick,
I think the taper I described will sag about 5 feet over the length of about 34
feet IF you were to hold the element horizontal at the 2 inch end. There are a
lot of 40m Yagi antennas that sag 3-5 feet from the center to the end. As a
meter of fact one that only sags 3 feet is probably a 50-60 pound element and
I'm not sure anymore commercially makes one that strong.
My vertical that I use about 15 feet from the water at ZF9CW is similar to this
taper schedule. On the occasion when the wind is not blowing it is pretty
darned straight and it is so light I can easily pick it up from the ground to
vertical in about 5 seconds. Unless someone were to tell me that if it were
moving by a foot or three when the wind is blowing off the open sea that it was
causing my signal to be down, I wouldn't care.
Mechanically, for me, it is not a concern at all. Is your concern the phasing
between the two verticals?
73... Stan, K5GO
> On Jan 1, 2020, at 8:11 PM, Richard (Rick) Karlquist <richard@karlquist.com>
> wrote:
>
>
>
>> On 1/1/2020 5:56 PM, Stan Stockton wrote:
>>
>> Less expensive and even lighter weight would be to start with a smaller size
>> and use longer lengths of smaller diameter stuff at the top. How strong do
>> you want it to be? If the wind speed is more than about 65 MPH at that low
>> height through the trees you probably have bigger problems than a bent 40m
>> vertical.
>> 73... Stan, K5GO
>
> What you describe risks excessive tapering
> that results in the top sections refusing
> to stand up straight even with no wind,
> as I described in a previous post in this
> thread. Been there done that.
>
> Rick N6RK
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