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Vertical ant experts, I need info

Subject: Vertical ant experts, I need info
From: steve.m.zettel@internet.nps.usace.army.mil (steve.m.zettel@internet.nps.usace.army.mil)
Date: Wed May 22 16:20:34 1996
     Steven (GREAT name!),
     Though far from an expert, here is my experience with tilted 
     I haven't yet modeled the tilted vertical in AO or NEC/Wires, but I've 
     used the Navy's standard 35' vertical whip (with autotuner located at 
     its base) for tactical and long-haul HF comms in several Inshore 
     Undersea Warfare Units, including a two-year stint as Comm Officer in 
     one of the units. Doctrine states, and is borne out by real-world 
     experience, that as the vertical is leaned over toward horizontal the 
     useful component of radiation becomes increasingly higher angle (and 
     somewhat attentuated). At almost horizontal the antenna is a NVIS 
     (near vertical incidence scatter) radiator, suited for close-in comms.
     In this mode, frequencies are varied to ensure that an appreciable 
     amount of signal is returned  to earth as ionospheric conditions 
     change throughout the 24 hour period. Some IUW units have gone as far 
     as to make base mounts that allow one of our two whips to be 
     continuously shifted from vertical to horizontal as tactical and 
     propagational conditions change. At small angles from vertical (to 
     perhaps 30 degrees off vertical) I've noted no perceptible difference 
     from a vertical radiator. At 45 degrees some effect is evident, as 
     much from the absence of distant stations as from any enhancement of 
     close in stations. As the antenna goes from 45 degrees to horizontal, 
     the effect can be dramatic--close in stations previously unreadable in 
     the "skip zone" can now be copied reliably. However, overall signal 
     strength often falls off too.
     The application for all of this would as a Sweepstakes antenna, where 
     long haul, low angle propagation would probably not be as useful as a 
     higher angle radiator. However, a medium to low dipole or horizontal 
     loop would serve as well, and have the advantages of higher efficiency 
     and less induced noise, particularly in the case of a horizontal loop 
     operated at it's fundamental frequency or second harmonic. The short 
     vertical operated over ground is a notoriously inefficient radiator. 
     We get away with using it in the Navy because of our (usually) close 
     proximity to the saltwater ground plane.  
     Two books on the subject of tactical HF communications, NVIS, and NVIS 
     radiators called, aptly enough "HF Tactical Communications, VOL I and 
     II" are available from Craig Clark's (N1XG) Amateur Radio Bookstore. 
     They are interesting reading, although the author does put in plugs 
     for equipment he or his company manufactures.
     Hope this helps. If I can be of further assistance e-mail me at this 
     address or kj7ch@libby.org
     Steve Zettel  KJ7CH                        kj7ch@libby.org
     Libby, MT USA                      steve.m.zettel@usace.army.mil

______________________________ Reply Separator _________________________________
Subject: Vertical ant experts, I need info
Author:  steven@zianet.com (Steven Nace KN5H) at Internet

What, if any effect does a 'tilt' in my vertical have in its performance? My 
R7, for lack of a better word, leans a lot. This less than vertical 
orientation is due to high winds. The question is, how much can I tolerate 
before there is a change in its performance.
Thanks in advance
73 de Hose  KN5H

>From WD8AUB@IX.NETCOM.COM (Douglas L. Klein)  Wed May 22 22:35:31 1996
From: WD8AUB@IX.NETCOM.COM (Douglas L. Klein) (Douglas L. Klein)
Subject: WPX
References: <Chameleon.960522152001.k4sb@k4sb.avana.net>
Message-ID: <31A388A3.6D74@IX.NETCOM.COM>

k4sb@avana.net wrote:
> For your information, all the calls I mentioned are perfectly legal to use 
> during
> 4-1-96 to 8-31-96. I'm not making up some phony prefix.
> -------------------------------------
> Name: ed sleight
> E-mail: k4sb@avana.net
> Time: 15:18:22
> This message was sent by Chameleon
> -------------------------------------


You missed the point.  But, it is probably just as well that you did....

>From tomf@neca.com (Tom Francis)  Wed May 22 23:50:54 1996
From: tomf@neca.com (Tom Francis) (Tom Francis)
Subject: IARU es CW Treaty requirement
Message-ID: <199605222250.SAA05333@orion.neca.com>

Greeting folks:

I am formally on the record with the FASC
as opposing the dropping of the CW treaty 
requirement as part of the IARU position
for WRC-99.

I've sent a message (snail and e) to the ARRL and
the IARU FASC concerning my opposition to the dropping 
of CW as a treaty requirment for member nations 
and will not repeat it here for the sake of 

However, I have waded through the 22 page "discussion"
paper and can not help but think that the CW issue
is closed and that in fact the CW will be deleted
as a treaty requirement for the amateur service.  Section
4 and and 9.12 through 9.14 are particularly telling.
It's done folks.

In any case, those of us who would prefer to keep
the CW treaty requirement should raise the flag and
let our IARU representative, in this case the ARRL,
know of our opposition.


Tom Francis, NM1Q (tomf@neca.com)

>From km9p@contesting.com (Bill Fisher, KM9P)  Thu May 23 01:31:22 1996
From: km9p@contesting.com (Bill Fisher, KM9P) (Bill Fisher, KM9P)
Subject: N6TJ's Swapping CQWW Weekends
Message-ID: <199605230031.UAA25701@paris.akorn.net>

I fully support NOT messing with CQWW.  I'm sure nothing will change, but
just in case they are thinking about it...

>From my perspective:

SSB contests should be during periods of more light.  If you really want to
switch some contests, the WPX weekends should be switched.  Moving the SSB
contest to a weekend where there is more dark, would mean moving the contest
(in spectrum) to bands that have less available (usefull) spectrum.  Which
means less enjoyment for the majority since only the biggest signals will be
able to occupy the small amount of spectrum.  Keeping SSB contests on 20, 15
and 10 is best.


Bill, KM9P
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