In a message dated 1/30/02 12:52:08 PM Pacific Standard Time, RLVZ@aol.com
writes:
> Second, the C-19XR is a very flimsy built antenna considering it's
advertised
> at "100 mph". The antenna flops around like a bird in full flight, and in
> my
> opinion, is not desirable for windy or coastal areas... such as here near
> Daytona Beach, Florida.
>
Okay, NO4S has made a claim that he knows absolutely nothing about -
flimsy is not a term used to describe wind survivability. Here's my response
to a previous private email from him:
>> > If you say the Force 19XR will take 100 mph then I'll take you at your
word..
> . though they sure look light-duty.
I said that they're modelled and designed for that spec. Every antenna is
put through the K7NV Yagi Stress modeling program which allows weak points to
be strengthened to meet various windspeed requirements.
> But the way the elements flap around I
> will not use one in a coastal area... such as here near Daytona Beach,
> Florida. I think hams need to be alerted that the Force 12's "flap around
> like a bird in full flight"!
So do other antennas with aluminum elements. F12 has introduced several
new mechanical design paradigms including aggressively tapered elements.
Sure, they're smaller and maybe they move a little but they totally do away
with low windspeed element vibration WHICH is a problem contributing to
element failure. Besides, you want everything to "bend like a willow" instead
of "breaking like an oak".
I'm a professional tower guy and have worked on over 150 different ham
stations and I don't have anything bad to say about F12 antennas -
electrically or mechanically (linear loaded antennas not included). >>
> The Hy-Gain TH-3 which you criticize there gains (perhaps rightfully so)
are
> a much stronger antenna than the Force. Therefore, while the Hy-Gain gain
> figures are less accurate than Force, I believe the Hy-Gain wind survival
> ratings are more accurate than Force.
Jeez - how do you know they're 'stronger'? What's your criteria? What are
your survivability criteria? Where are your calculations?
I never criticized a Hy-Gain TH3. If you're going to put words in my
mouth, please get them approximately right.
>
> W8JI makes a good point when he states "don't believe antenna
specifications"
>
He was referring to electrical specs.
Sorry, Richard, but you don't know what you're talking about. None of
your comments have any basis in fact - they are just your non-technical
observations. You sound like a good candidate for a Mosley beam - they're
strong enough for you (and a wise investment too - sarcasm intended).
Cheers,
Steve K7LXC
Tower Tech
________________________________________________________________________
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