Topband: Confusion in ON4UN's Low Band DXing radiallengthcalculations.

[k1fz at myfairpoint.net]

     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 at 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 at 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 at 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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