Hi John,
In a message dated 96-03-21 21:52:34 EST, you write:
>Here is my experience. I have been using beverages for more than 25 years. I
>have a 4 square for 80 since 3 years, and a single 1/4 wave vertical for
160.
I have also been using them for a similar time period, since the early 70's.
>On 160 I always use the Beverages. They are so vastly superior to the
>vertical, that I NEVER use the vertical. I have 12 Beverages, one per 30
>degs, and each is 600 to 1100 ft long (approx), and 6 ft high.
That's interesting. My experience is that in a quiet rural location, the
Beverage is very little improvement over a simple vertical. Perhaps 3 or 4 dB
at maximum when there is no QRN from storms. But in a suburban location the
difference was always larger. Four end fire loops (an array two hundred feet
long) ALWAYS beats the 500 ft or longer Beverages.
>On 80, the Beverages outperform the 4-square 98 % of the time. I must admit
>though that my 4-square is NOT optimized for maximum low angle. Using
>(intentionaly!) only one radial on each vertical. I have some high-angle
>radiation from the array, which of course deteriorates its receiving
>performance. It was done intentionally as to give our signal a little more
>"presence" in Europe during contests. If I had not Beverages, I would
>probably not have done this. The 4-square will only beat the Beverages hours
>after sunrise of hours before sunset, when the signals are so weak that I
>need the additional gain of the 4-square.
I understand your goal, it's a great idea during transmitting.
But how do you prevent the four square from picking up feedline noise with
such a poor grounding? And certainly the intentional high angle response
destroys some of the directivitity responsible for low noise and QRM on
receiving! On 20 meters I feed a vertical mounted above my beam with 6 dB of
power division to keep locals away. But I think these systems make very poor
receiving antennas! On 20 I disconnect the vertical when receiving, but you
can not disconnect your single radiating radials!!
>BTW, the 1100 ft long Bevberags ALWAYS outperform the short ones. In my case
>1100 ft is definatley not too long, not even for 80 meters.
When I measure the current here on a 500 ft Beverage, the power loss is 6dB
per 500 ft. In high conductivity soil the loss was only a little less. I
suspect the reason my reception has never improved with a longer antenna is
the large loss. Comparing a 500 foot Beverage to a longer Beverage made no
difference at all in A/B tests here, except for normal diversity fading that
only lasts a few minutes.
As a question John, I wonder if perhaps sometimes Beverages are not
terminated as well as they could be? In that situation, longer lengths would
improve termination and reception from the lowering of standing waves by the
added losses.
Many people find 4 squares better or even two element vertical arrays better,
that seems to be the rule rather than exception. I know that a dipole at 300
feet always beat any Beverage I had, and four small loop antennas in an end
fire array also do that.
But since good ways to model or measure receiving antennas are difficult to
find, it's a lot of peoples gut feelings, hi. I also wonder how much
information comes from antennas that are not installed correctly, with proper
feedline decoupling and so on. I never hear of people decoupling feedlines on
Beverages, and that is very important unless the feedpoint grounds are *very*
good.
73 Tom
>From ke6ynn@MasPar.COM (Mt Greylock Exped Force KE6YNN/WA1MUG) Fri Mar 22
>07:19:04 1996
From: ke6ynn@MasPar.COM (Mt Greylock Exped Force KE6YNN/WA1MUG) (Mt Greylock
Exped Force KE6YNN/WA1MUG)
Subject: WPX portables
Message-ID: <9603220719.AA23502@greylock.local>
> You do not have to sign /1. If you do, you become KE1.
Yep.
> I would stay KE6BER and not sign /1 as a Six prefix will a little rarer
> on the east coast.
Hmmm. I don't think they've issued KE1's yet, so that'd be rarer than a
KE6. BUT if not many people realize that KE6/1 = KE1, then not many will
realize how rare you are! Not much value in that!
73. --John/K2MM
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