Topband: Do short beverages "work"?

[WD8DSB at aol.com]

Rick N6RK wrote :
 
It would be interesting
to see if really short beverages exhibit  these nulls.  Otherwise,
useful as they may be, they are acting a  degenerate low dipoles,
but still beat listening on the transmit  antenna.

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I too wondered what the pattern of the beverage looked like as its  length 
was reduced so I did a simple model using EZNEC demo for a terminated 1.8  
MHZ beverage (500 ohm termination) mounted 5 feet above ground using a ground 
 conductivity of 0.005 S/m, for beverage lengths of 150 feet to 550 feet in 
 increments of 50 feet, and I created a simple website where you can  view 
the progression of the patterns (3D pattern looking down at the  pattern 
from above).
 
The website URL where you can view the patterns I created is 
_https://sites.google.com/site/beverageantenna/_ 
(https://sites.google.com/site/beverageantenna/)  and  if you click on a pattern it will expand in size for easier 
viewing.
 
I am by no means an expert on using EZNEC, but I believe the plotted  
patterns do provide insight into the behavior of the beverage at different  
lengths.  It looks to me like lengths of 300 feet or more start to  become very 
interesting (using the parameters I used) but this does not mean  shorter 
lengths are not useful (similar to what Rick said), but will let  everyone draw 
their own conclusion from the plots.
 
Note : the 500 ohm termination provided a reasonably flat SWR versus  
frequency regardless of the lengths I used when analyzed from 1 to 7  MHZ.
 
73's
Don (wd8dsb)