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Re: Topband: What ever happened to the 160 meter "Z" antenna?

To: Tom W8JI <w8ji@w8ji.com>
Subject: Re: Topband: What ever happened to the 160 meter "Z" antenna?
From: Stan Stockton <wa5rtg@gmail.com>
Date: Tue, 17 Feb 2015 06:16:15 -0600
List-post: <topband@contesting.com">mailto:topband@contesting.com>
A good analysis of all this can be found from IV3PRK as he planned his antenna 
for his new QTH in HC land.

http://www.iv3prk.it/user/image/site2-inverted-l-vs-vertical-t.pdf

73...Stan, K5GO

Sent from my iPad

On Feb 16, 2015, at 6:14 AM, Tom W8JI <w8ji@w8ji.com> wrote:

>> Tom,  Thanks for the details on the "Z" for TB.  On a related matter I have 
>> been looking for comparisons between a "L" and a "T" firmly believing that a 
>> "T" would be better as in 65' up and 135' horizontal fed in the exact 
>> center.  However there are so many TB'ers using "L" rather than "T"s which 
>> begs the question....why? You need two supports for the "L" but how much do 
>> you gain by converting this to a "T" with even a modest ground plain of 6-12 
>> radials?  Or is it just a matter of convenience and lot size?
> 
> There is almost no difference between the T and L. It is mostly a matter of 
> what someone can fit.
> 
> When I lived on a city lot, I had restricted antenna room. I installed a 
> "G5RV" between two tall pines. I dropped the feedline vertically to the 
> ground. I fed the entire thing as  T on 160, and I managed to work many JA's, 
> VU, UA0's, VS6, and even a JT on 160.  An L I tried was no different, but too 
> many wires cluttered an area and makes an RF mess out of things. The G5RV 
> gave me a good 160 antenna (fed as a T) and a pretty good 80-10 antenna, with 
> just one wire and one feedline, using a tuner right where the feeder came to 
> ground level.
> 
> I installed a 100 ft vertical later, and it was no better than the G5RV "T". 
> As a matter of fact I just phased the 100ft tower against the G5RV to make a 
> two element 160 vertical array with four patterns.
> 
>> Again my question:  How much better is a "T" over an "L" on 160?
> 
> No one would notice, it is not even worth one dB. We are actually lucky to 
> notice 6 dB unless we A B test something.
> 
> You would likely notice the out and up and out half wave, though. It is far 
> more like a messed up dipole than a good vertical.  The one I tried lost 
> several dB on groundwave over a base loaded vertical. It kept getting better 
> and better as I made it more and more like an "inverted L". 
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