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Re: [TowerTalk] EZNEC- needs improvement

To: Jim Brown <jim@audiosystemsgroup.com>
Subject: Re: [TowerTalk] EZNEC- needs improvement
From: jimlux <jimlux@earthlink.net>
Date: Sun, 19 Apr 2009 07:32:02 -0700
List-post: <towertalk@contesting.com">mailto:towertalk@contesting.com>
Jim Brown wrote:
> On Sun, 5 Apr 2009 16:00:50 EDT, RLVZ@aol.com wrote:
> 
>> Yes- do have poor performance with verticals, but you mentioned that you  
>> live in a heavily wooded area.  Verticals work poorly in heavily  wooded 
>> areas so I don't believe that's a fair environment to compare verticals 
>> to horizontals.
> 
> I've looked for published scientific work on this and all I've found 
> addresses VHF/UHF (either military, 2-way, or cellular applications). What 
> I've seen generally agrees that absorption that increases with frequency, 
> and that correlates with my experience. Can you point me to anything that 
> addresses MF or HF in forests and heavy vegetation? 
> 
> 7

Your best bet is to look for reports produced in the 60s and 70s in 
connection with the Vietnam War.  George Hagn, among others, when he was 
at SRI did a lot of tests.  Most doesn't show up as pubs in IEEE 
journals, but is in various DTIC stuff.

That said, I don't recall seeing much.

There's also some papers by Caviolotti(sp?) on propagation in layered 
inhomogenous media (which is what a forest over ground is) in Trans on A&P.

I'll see if I can dig up some references next week.
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