Topband: Beverage termination

[Sam Dellit]

g'day hal

the introduced vertical component is very important generally.
problem is the beverage desired pickup is the travelling/surface/crossfield
wave which is typically 5-10 percent of the actual vertically polarised wave.
so that 9ft of vertical gives comparable pickup to 90ft to 180ft of beverage
pickup. if you are looking for the best front to side and front to back, you
really need to attend to this (but don't let that deter you from using one,
they are still most excellent receiving antennas without the bells and whistles)
if the beverage is the right length the vertical components from termination
and receiver connection may largely cancel due to phasing but if murphy's
law still applies they wont.
i don't believe that sloping the termination helps much electrically though
it certainly simplifies the physical termination, even with a slope the
resolved 
total vertical component is the same. i think misek tackled the problem with 
balanced open wire feeders at both ends.
more recently i believe un-uns have been utilised to allow coaxial feeders
at both ends.

73s

sam dellit vk4zss


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