thompson@mindspring.com wrote:
> << There have been several messages on a half wave verticals not needing
> radials. Any vertical works better with radials. >>
I disagree! Quarter wave antennae REQUIRE a counterpoise' to produce an
equal but opposite `image' of the elementto be an ANTENNA. Two quarter WL
antennae stacked with the feed points together produced a dipole A pipe in
the ground is not a counterpoise, because of the high resistance of the
dirt. (salt water excepted)
37 + 37 = 72 OHMS
A vertical half wave element (which can be feed at either end with proper
matching, if you wish) can be elevated any amount you wish , if over the
houses and trees this will reduce the effects of the ground clutter, is
unsurpassed. IMHO
> << A vertical dipole will work OK with center feed, but feeding at the base
>
> with radials attached will work even better. >>
If you don't match the 5 k or so input impedance it won't. Radials do
little, to a dipole, but change the radiation angle, and possibly detune it
comparing it to it's `mounted high away from everything frequency.'
73 (= Best Regards) de: Ron ka4inm@qsl.net
VISIT my HAM WEB SITE at: http://www.qsl.net/ka4inm
using LINUX here & loving it!
--
FAQ on WWW: http://www.contesting.com/towertalkfaq.html
Submissions: towertalk@contesting.com
Administrative requests: towertalk-REQUEST@contesting.com
Problems: owner-towertalk@contesting.com
Search: http://www.contesting.com/km9p/search.htm
|