[TowerTalk] Basic Question about Antenna Height and Treetops

[Marsh Stewart]

My 80M loaded vertical is about 10 feet from the closest pine tree. It
starts at about 9 feet above ground and runs straight up to 70 feet. In the
middle of the vertical element there is a small loading inductor. Below the
vertical element there is a FCP - 18 feet on each "side" (36 feet total
"width") with 6 inch spacing between the horizontal FCP wires. Not ideal,
but it's the best I can put up in my backyard in a residential subdivision.

I worked both North Cook and Chesterfield this morning on 80M CW using that
antenna for both transmit and receive. That does not mean it is a great 80M
antenna, but it sure "works"....at least a little.

73,
Marsh, KA5M
    

-----Original Message-----
From: TowerTalk [mailto:towertalk-bounces at contesting.com] On Behalf Of Jim
Brown
Sent: Tuesday, October 06, 2015 10:34 PM
To: towertalk at contesting.com
Subject: Re: [TowerTalk] Basic Question about Antenna Height and Treetops

On Tue,10/6/2015 4:51 PM, K1JOS wrote:
> I am moving to a home situated on a hilltop.  Nearest same height hilltop
or
> higher is about 1 miles away.  The home is surrounded by dense (typical
New
> England Forest) 80' high hardwood and fir trees and my planned small tower
> (budget and local codes) gets me only to a 50-60' antenna height.  The
trees
> will be within 50- 75' from my nearest Yagi ends.   How badly can I expect
> my signal to be affected by the higher surrounding tree tops?

Not at all below 2M.  Hilltops are wonderful for HF -- I've operated 
from several. My antenna farm is in the middle of a very dense redwood 
forest. The trees hold my 80/40 dipoles at 140 ft, they tower at least 
50 ft above my 3-el SteppIR, which is at 120 ft. Except for 160M, all my 
antennas are horizontal. 160M antennas are verticals.

Another point of interest. Hilltops often have poor soil quality. That 
makes them bad for verticals, because verticals need both low loss under 
them and low loss at the first reflection.  Verticals are also more 
affected by trees.

I strongly agree with K4XS that you should use HFTA EXTENSIVELY. I put 
hundreds of hours into it.

73, Jim K9YC

_______________________________________________



_______________________________________________
TowerTalk mailing list
TowerTalk at contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk