[Antennas] Dipole Height

Ray Brown kb0stn at sbcglobal.net
Thu Sep 17 19:49:20 EDT 2015


 Just what I said, Ray! 
 Ray, KB0STN
----- Original Message ----- 
From: "Ray, W4BYG" <w4byg at att.net>
To: <antennas at mailman.qth.net>
Sent: Thursday, September 17, 2015 9:42 AM
Subject: Re: [Antennas] Dipole Height
>I don't think I agree with this suggestion.
>> At 40 meters typical RG-8 cables losses are much less for 90' to 100' of 
> cable, than the significant gain in low angel of radiation that would 
> occur with the higher installation. RG-8 cable loss at 7.2 MHz for 100' 
> at a VSWR of 1:5 to 1 are about 1/2 db. See:
>> http://www.kc7hxc.us/links/radio/Coax%20Calc/Coax%20Calculator.html
>> With antenna height of 7' AGL most of your energy is NVIS and going 
> straight up and down warming the clouds and worms. At 90', most of your 
> energy is going out on the horizon at good angles where it should be, 
> for DX contacts.
>> Big difference!
>> 73,
> Ray, W4BYG
>>> On 9/17/2015 10:05 AM, David Robbins wrote:
>> once you factor in the extra loss for the feedline needed to get it up that high the improvement will be negligible.
>>>>>> Sep 17, 2015 09:34:15 AM, jkolin at optonline.net wrote:
>>>>>> Hey Ray,
>>>>>> Will my 40 meter dipole work better for DX at 90 feet above ground
>> instead of 7 feet above?
>>>>>> Jay...NE2Q
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>>>>> -- 
> I'm no longer young enough to know everything!
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