these are only starting points! Local conditions - the antenna itself, the
surroundings, the ground, etc etc will all conspire to move that value up or
down slightly. KNOWING what your particular antenna is in place - that is
the perfect starting point.
g.
-----Original Message-----
From: V. Sciucka
Sent: Wednesday, September 13, 2017 2:46 PM
To: Chuck Dietz
Cc: Charles Morrison ; towertalk@contesting.com
Subject: Re: [TowerTalk] 80m vertical size calculation
I just thought that it might explain why different formulas are used.
Charlie gave me formula which is widely available: 246/f(mhz) = element
(feet), but I also found https://www.dxengineering.com/
techarticles/verticalantennainfo/dx-engineering-comtek-verti
cals-for-phased-arrays (see p.5) where 234/f(mhz) is used.
--------------------
Vytenis
2017-09-13 21:33 GMT+03:00 Chuck Dietz <w5prchuck@gmail.com>:
Maybe I don't understand, but I would think that if you had a tower with
an aluminum tube "stinger" on top, this might not work because of the
change in percentage of the various diameters.
Chuck W5PR
On Wed, Sep 13, 2017 at 1:00 PM Charles Morrison <junkcmp@gmail.com>
wrote:
Not length to diameter, It is independent of diameter.
It is a simple method to determine a difference of length as a ratio
based
on frequency.
On Wed, Sep 13, 2017 at 11:41 AM, V. Sciucka <vytenis.sciucka@gmail.com>
wrote:
> Thanks Gary K9RX and Charlie N1RR, 2nd question is clear now.
> Charlie also gave formula for length 246/f(mhz) = element (feet) which
I
> assume includes length to diameter ratio or this ratio is not so much
> important.
>
> --------------------
> Vytenis
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