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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