Guys, this has definitely been one of the more interesting threads on
towertalk I can remember! For me more an intellectual exercise than
reality!! .....I mean, I've been chuckling all this time....being a ham of
modest means I can only dream of a "real" tower higher than 40' -- my Force
12 C3 sits atop a roof-mounted 9' tower which isn't much vertical clearance
for the antenna but it stills makes it to Europe/Asia etc....when the bands
are open, needless to say!!
Some day when my 6 numbers come up in the lottery I hope to have such a
dilemma whether to put the yagi at 40', 90' or 160....or maybe a beam at
each height......Y I K E S!!!
Good dxing to all.......
>From: David O Hachadorian <k6ll@juno.com>
>On Fri, 11 Jan 2002 17:40:38 -0800 (PST) Michael Watts <wy6k@yahoo.com>
>writes:
> > If a lower antenna is better only in some small percentage of cases,
> > then it's not wise to advise
> > a one antenna guy to put the antenna lower. There seems to be
> > substantial agreement that higher
> > antennas perform better a larger percentage of the time than lower
> > ones. Is this not true? If
> > you had only one antenna, would you put it lower or higher?
>
>If you have only one antenna you should definitely put it
>lower.
>
>If you take a quick look at antenna patterns, you will see that
>the higher the antenna, the narrower the lobe.
>
>A low antenna (50' 20M) is 3 db down from a high antenna
>(90' 20) at the lowest angles.
>
>But, the high antenna will have a 30 dB null in the middle of prime
>arrival angles (90' 20M, 22 degrees). You will get KILLED much
>of the time.
>
>Which would you rather have, -3dB or -30dB?
>
>If you have only one antenna it should be less than:
>50' on 10M
>70' on 15M
>90' on 20M
>50' for a tribander during sunspot maxima. Minima 70'.
>
>Now some of this depends on what type of operating you do.
>Contesters have to work EVERYBODY, ALL THE TIME (ALL the
>angles).
>DX'ers are happiest when they are the first to get through
>on some difficult propagation path (The lowest angles).
>
>The best answer is to download YTAD and figure it out for
>yourself.
>
>Dave Hachadorian, K6LL
>Yuma, AZ
>K6LL@juno.com
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