Antenna resonance (and SWR bandwidth) are affected by conductor
diameter. I don't understand why we continue to rely on formulas
assuming wire as the conductor when it is trivially easy to model a
vertical monopole in programs like NEC that can take conductor diameter
into account (and can do a LOT more). Modeling and measurement can be a
great teacher -- they certainly have been for me.
I use W7EL's EZNEC because I find it easy to wrap my head around the
user interface. It's not free. Others prefer 4NEC2, which is free, but I
don't like the user interface.
73, Jim K9YC
On 9/13/2017 11:46 AM, V. Sciucka wrote:
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.
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