W1KM found that out as they didnt work at all stretched over a saltwater
marsh out on his Cape Cod contest station
A Beverage needs a relatively poor ground to slow down and tilt the incoming
wave.
On my extra poor ground rock pile Im amazed at how well they work once I
understood the nuances of proper matching and establishing a steady ground
reference. If I had run a ground wire end to end as some texts state I would
have lost most of the directivity.
Carl
KM1H
----- Original Message -----
From: "GeorgeWallner" <aa7jv@atlanticbb.net>
To: "Robin" <wb6tza@socal.rr.com>; <topband@contesting.com>
Sent: Friday, April 22, 2011 7:45 PM
Subject: Re: Topband: Beverages near the ocean
> On Fri, 22 Apr 2011 16:01:35 -0700
> "Robin" <wb6tza@socal.rr.com> wrote:
>> I like your definite answer: It Depends! Truly!
>>
>> It unfortunately seems a bit complex to make a rule
>>other than build it and see! Your experiences match what
>>I would expect, but there seems to be more at work than
>>just distance to seawater.
>
> Robin,
>
> Our experiences match closely.
>
> One key point I tried to make was that whether a Beverage
> will be good or not depends on its distance from the sea
> water. Not only its lateral distance but also its vertical
> distance. If there is sea water under the sand under the
> Beverage, it will most likely not work well. In several
> cases, I have actually dug down to see if there was sea
> water! On Chesterfield, while there was water under the
> sand, it was fresh water! Rain water got trapped between
> the underlying rock and the sand. The Beverage above it
> worked well. It was a reversible Beverage and it had a
> very good F/B. Also, its signal to noise ratio was better
> than our 60' DHDL's. A very similar Beverage that ran
> parallel to the beach did not work: its signal to noise
> ratio was worse than the DHDL's. And, just like you said:
> it was a low noise omni-directional antenna with very weak
> signals. There was salt water under that beverage: the sea
> essentially just continued under the sand.
>
> One now has to ask which is easier? To build the Beverage
> or just dig down 3 to 4 feet to see if there is sea water?
> (I would build the Beverage: I hate digging and like
> building antennas.)
>
>
> 73,
>
> George, AA7JV
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
_______________________________________________
UR RST IS ... ... ..9 QSB QSB - hw? BK
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