Look at the radial field as a FAT inductor. A fat tower has a
lower Q and wider bandwidth, lower impedance at the top/far end.
73
Bruce-=k1fz.
On Sun, 21 Dec 2014 10:10:32 -0500, w4buw@aol.com wrote:
GM BRIAN... I HAVE BEEN OFF TOP BAND FOR SEVERAL YEARS NOW,
AND NOT AS ACTIVE AT AGE 76 AS I ONCE WAS...
GOING BACK TO MY OLD EE DAYS, IF Q=X/R, DOESN'T Q INCREASE IN VALUE
AS R DECREASES IN VALUE? SEE YOUR COMMENT I HAVE UNDERLINED AND
PLACED IN BOLD FONT BELOW...
73 DE GEORGE, W4BUW
-----Original Message-----
From: k1fz
To: Topband
Sent: Fri, Dec 19, 2014 3:56 pm
Subject: Topband: Confusion in ON4UN's Low Band DXing
radiallengthcalculations.
The on/in ground wire- as RF advances toward the normal 1/4 wave high
impedance (/high voltage point) finds itself tightly coupled to a +-
350 ohm typical ground resistance. 'Hogs the voltage right down'
Many Shorter radials do not develop enough high voltage, not
reaching 1/4 wave.
Multiple radials divide the loss like resistors in parallel. lowering
the Q, lower impedance, with lower voltage, being pulled down
results in less voltage leakage at the far ends.
73
Bruce-K1FZ
www.qsl.net/k1fz/beveragenotes.html
On Fri, 19 Dec 2014 12:21:12 -0500, k8bhz@hughes.net wrote:
I can’t agree with this “conventional” thinking. Why does a piece
of wire magically lose it’s length just because you lay it on the
ground? The electrical length changes because of Vf, and it’s
resistance changes because of the lossy ground, but it’s still a
piece of wire. I’m going to try to attach a posting I did back in
2006. If it doesn’t work, I will follow with a separate posting.
>
> Brian K8BHZ
>
> From: Tree
> Sent: Friday, December 19, 2014 10:07 AM
> To: Doug Turnbull
> Cc: k8bhz@hughes.net ; 160
> Subject: Re: Topband: Confusion in ON4UN's Low Band DXing radial
length calculations.
>
> Radials on the ground do not have a magic length. Worrying about
resonance for them is not necessary.
>
>
> If you tune a quarter wave wire up in the air - then lay it onto
the ground - it couples to the ground and is no longer a distinct
single piece of wire. Just make them an easy length to deal with and
put as many of them down as you can.
>
>
> Tree N6TR
>
>
----- End forwarded message -----
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