I've found that a fairly easy to transport and erect antenna for portable
operation is just a center fed vertical dipole using 450 ohm line and a true
(i.e. not just a balun on the feed line) balanced antenna tuner. Same
general rules apply - no more than 1.25 wavelength at highest frequency and
at least about 0.6 at the lowest. 40-45 feet has worked foe me on 10-40
meters. Then, if I really want to get on 80 at night, and there is room,
I'll add 100 feet or so to the top. The vertical dipole has the obvious
advantages of not needing to worry about radials and being a low angle
radiator. I have even had fairly good results on 10-20 with a 20 foot
centerfed vertical with some "T" loading on top and bottom.
Gene / W2LU
----- Original Message -----
From: "Rick Karlquist" <richard@karlquist.com>
To: <k0rc@citlink.net>
Cc: <towertalk@contesting.com>
Sent: Sunday, April 24, 2011 7:21 PM
Subject: Re: [TowerTalk] TowerTalk Digest, Vol 100, Issue 63
> Robert Chudek - K0RC wrote:
>> Jim Brown, K9YC wrote: "BUT - in my experience, vertical dipoles don't
>> work very well on the HF bands."
>>
>
> It is difficult to feed a vertical dipole in the traditional
> way in the center without the feedline affecting the pattern.
> It is also tricky to feed it from the bottom, as a half wave
> vertical. I did some direct A/B tests comparing a 1/4 wave
> vertical to a 1/2 wave vertical on 20 meters. They were
> virtually indisinguishable, with maybe a slight edge going
> to the 1/2 wave vertical. You can call that a vertical dipole
> if you want. It had no radials by the way, while the 1/4 wave
> vertical had 32 1/4 wave radials. YMMV.
>
> Rick N6RK
>
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