Topband: Modeling the proverbial "vertical on a beach"

[john at kk9a.com]

As I recall, ZF1EJ's station uses a log periodic, a tribander and possibly
other antennas and he is on the southern side of the island.  Log periodic
antennas typically do not have much gain if they were using that.  While
there is no proof that I am aware of, stations new the sea facing their
target zone, like D4B/D4C, CU2X, VY2ZM etc do exceptionally well.

Verticals on the beach are great for expeditions.  In March 2000, I set up
two 40m verticals on the northern beach of Grand Cayman (one was a parasitic
element) and also a low 40m dipole and the verticals were 10dB louder than
the dipole.  I am sure that a high beam would be better, however this
suitcase station was good enough to win a contest plaque. 

John KK9A - P40A

To:	Juan EA5RS <ea5rs at ono.com>
Subject:	Re: Topband: Modeling the proverbial "vertical on a beach"
From:	Stan Stockton <wa5rtg at gmail.com>
Date:	Sun, 17 Aug 2014 07:03:02 -0500

I know what I am going to say isn't talking about 160m, but pertains to a 
vertical on the beach.

Quantifying, with anything but anecdotal data, the difference between a 
horizontal antenna located inland versus a vertical on the beach would take 
something more than a short experiment but here is another experiment that
uses 
RBN.

My son, ZF2DX, is living in Cayman Islands.  I went down in May and we
planned 
to operate from the beach in the WPX Contest.  On Friday I was in the
process 
of putting up some simple verticals when we were asked whether we would like
to 
join a small group at ZF1A.  They would change category to M2 if we would 
operate with them instead of operating separately with both in MS category.
We 
decided air conditioning would be nice and it would be fun to try to win the
M2 
category so I took down the verticals and we joined them.  

Sunday afternoon when Kevin and I were finished with our operating time
slots 
we decided to go to the beach for about an hour, put up a 15m vertical with 
only two radials, use 100w and then look at the RBN.  ZF1A was on 15m using
a 
Yagi at 100 feet pointed toward Europe and 1200w power.  We compared spots
at 
the same time to a large number of Skimmer stations. As I recall in some
cases 
we were in the range of -2 dB to -0 dB on some comparisons and in no case
were 
we down more than about 5 dB.  Having both operated from the big station all

weekend, we both walked away from the beach before ever looking at the RBN
with 
the belief that it was a big improvement, just using a 12 foot vertical with

two radials. That belief was reinforced after we compared using RBN.  If
ZF1A 
had been using 100w instead of 1200w and a single, ground mounted vertical
with 
any number of radials instead of the Yagi at 100 feet, I can only imagine
how 
much stronger we would have been.

I was converted into a believer and would not need specific quantitative
data 
to know that with very little effort I could put up some simple antennas on
the 
beach and be competitive with a large station with horizontal antennas
located 
inland.  In fact give me about 6 dB over a single vertical on the waters
edge 
and you would need a very large station located inland to compete.  

73...Stan, K5GO