[TowerTalk] Beverage vs what?

[K7GCO@aol.com]

In a message dated 11.01.00 10:35:23 Pacific Standard Time, 
n4zr@contesting.com writes:

<< 
 Even though I have 5 acres of land to work with, the shape of the property
 is such that the longest Beverages I can install, aimed at either Europe or
 North Asia, are less than 300 ft long.  My reading suggests that this is
 probably too short for 80 meters, and certainly for 160.  With that in
 mind, I'm looking at alternatives.
 
 My current transmit antenna on 80 is a 4-element K3LR-style parasitic
 array, whose pattern closely resembles a 4-square.  The problem is that the
 patterns of a short beverage, a EWE and a K9AY loop look just about the
 same as that of my transmit antenna.  Gain aside, I'm wondering if I can
 expect any better signal to noise performance from them than I now get
 listening on the transmit antenna.
 
 There are some anecdotes suggesting that a Beverage works better than its
 pattern would suggest because it discriminates against vertically polarized
 energy, which my transmit antenna clearly does not.  Anything to this?  I
 found no discussion of this phenomenon (?) in ON4UN's book.
 
 Finally, if a Beverage really is meaningfully better, has anyone compared a
 traditional Beverage of the right length to a helical "Slinky" Beverage?
 
 73,  Pete N4ZR
  >>
    I have a place in SD with about the same size and concerns.  I've seen 
short Beverages work great perhaps due to the better S/N ratio and feel very 
confident to try them.  One of them on 160M was about 250' long and even 
reversible here in Seattle.  It was even mounted 3' over a 6' high fence 
which may have enhanced its performance.  I was going to even run radials on 
the ground under Beverages although that might upset some Beverage 
characteristic.  It should be equivalent to higher conductivity ground.  The 
closeness of radials may act like open wire transmission line with current 
and phases such that there could be some conciliation affect--that's .02 WL 
spacing.  The 160M reversible Beverage on the 250' fence shows it might 
work--perhaps better.  It might not be a problem on 40M or just 1/4 less.  I 
have tested transmission line antennas in Eznec and know the affects of 
various spacings.  I've never heard of anyone running passive radials under a 
Beverage.  I'll try it in Eznec along with controlling its phase by feeding 
it.  
     I'll be able to run the radials beyond the end also.  I've run 10 
radials 550' and longer in favored directions in Eznec for a 1/4 WL vertical 
and a vertical beam and I got 4 dB gain.  If very long radials beyond a 
Beverage helps a vertical beam, perhaps it will help a Beverage.  It's worth 
a try.
    There is another way to increase the gain about 3 dB of any LW and I just 
did it for a 550'  LW 50' high in Eznec.  Then I used 2 of this configuration 
with 3 dB more gain each in a Vee Beam configuration and ended up with 21 dB 
gain over perfect ground (reflection gain added).  The lobe was very sharp on 
10M and therefore somewhat limiting since it was not rotatable.  The sharp 
high gain lobe would not be the case on 160M.  This is the highest gain I 
ever obtained for wire antennas and is a great concept.  I get about 17 dBi 
gain from a 10M-7 element yagi 50' high over perfect ground for comparison.  
This new design Vee Beam gain figure was for 10M but the gain increase for 
any shorter LW (or Beverage) will be the same for a single configuration or 
in a Vee Beam configuration.  I will try it in Eznec and in SD and keep you 
posted.  Has anyone run regular Vee Beam Beverages?  I about rose out of the 
chair when I read your post and its similarity to my SD QTH and a way to 
increase the gain of a short or any Beverage.  You immediately oriented my 
thinking from 10 to 160M for this gain increase idea.  There indeed appears 
to be finally an easy way to increase the gain of a or any length Beverage.  
It works with a LW at normal heights.  I'll try it-I'll try it.  
k7gco

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