On Wed, 11 Sep 1996, Jeffrey Herman wrote:
> This thread is fascinating. But in almost all descriptions I read of
> the Beverage being close to earth. What if one is able to get the
> wire elavated, say at 50 feet, for it's entire length? Does the
> impedance change? (Of course, at 160M even 50 feet is "close to
> earth.") Is there any advantage, electrically, to have the wire
> low?
The directivity of a Beverage degrades steadily as it is raised;
conversely its efficiency improves steadily as it is raised.
Most Beverage users prefer good directivity rather than good efficiency,
so low heights are preferred (less than 8 feet on 80 and 160M). Even
lower height is needed to preserve Beverage directivity on higher
frequency bands.
A 160M Beverage at 50 feet is not a Beverage at all, its just a long wire
with reasonably good efficiency compared to a Beverage, but with no
useful directivity for receiving DX signals.
73!
Frank
W3LPL
donovanf@sgate.com
--
FAQ on WWW: http://www.contesting.com/topband.html
Submissions: topband@contesting.com
Administrative requests: topband-REQUEST@contesting.com
Sponsored by Akorn Access, Inc & KM9P
|