T hanks for the correction, Stan. My old eyes missed that!! A 90' tower won't
require much top-loading at all!
Sorry for my error
73,
Charlie, K4OTV
-----Original Message-----
From: Stan Stockton [mailto:wa5rtg@gmail.com]
Sent: Wednesday, February 04, 2015 1:41 PM
To: Charlie Cunningham
Subject: Re: Topband: [Bulk] Top Loading wires
It's a 90 foot tower he is describing.
Sent from my iPad
> On Feb 4, 2015, at 12:11 PM, Charlie Cunningham
> <charlie-cunningham@nc.rr.com> wrote:
>
> Gee, I surely agree with Grant, Larry! I've used EZNEC for MANY years, with
> great results, and I've designed, built, tested and measured many wonderful
> EZNEC designs - including some really complex "killer" antennas!
>
>
> I do think that 28' top loading wires will be WAY TOO SHORT atop 50 ft. of
> Rohn 25! More like 50-70' will be needed to resonate that tower. You will
> probably do just as well with TWO top-loading wires in a Tee configuration!
> The point is for the top-loading wires to extend the tower to 1/4 wave
> resonance on 160. Of course you could make an excellent 80m antenna with the
> 50' tower and some modest top-loading wires approaching the length that you
> are considering. GL!
>
> If you are going to be experimenting with low-band antennas, EZNEC is a GREAT
> investment
>
> 73,
> Charlie, K4OTV
>
> -----Original Message-----
> From: Topband [mailto:topband-bounces@contesting.com] On Behalf Of Grant
> Saviers
> Sent: Wednesday, February 04, 2015 11:28 AM
> To: Larry - K1UO; Topband Reflector
> Subject: Re: Topband: [Bulk] Top Loading wires
>
> With an insulated tower, the cheapest EZNEC and other free NECs will yield
> good results. Would you rather climb, cut, and trim a few times or spend $89
> to get EZNEC? Simple to learn. And the demo version is free eznec.com
>
> Grant KZ1W
> no affiliation, just a long term happy user
>
>> On 2/4/2015 7:27 AM, Larry - K1UO wrote:
>> Could someone tell me the length of top loading wires (4 wires planned)
>> needed to add to the top of a base insulated 90 foot Rohn 25g tower to
>> maximize the radiation resistance on 160 meters. I understand there is a
>> point of diminishing returns on the top loading lengths. The 4 wire angles
>> will be around 45 degrees or as close as possible. If I knew how to model
>> ,or even had a modeling program, I would attempt this already relatively
>> simple task to many.
>> From 50+ years of practical experience, I am ‘guessing’ maybe 28 feet long
>> each?
>>
>>
>>
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