That's good news. I am in Saudi Arabia on a small lot. My plan is to use my
ladderline-fed Cobra Ultralite dipole (73' long), tying the 100' ladderline
together, making a T. Will load it against a decent ground via a wide range
tuner.
Thoughts?
Thanks,
Ed 7Z1ES
> On 20 Feb 2020, at 7:45 AM, GEORGE WALLNER <aa7jv@atlanticbb.net> wrote:
>
> The T has another advantage: it is better on 80 (and 40) if you can match
> it. A 160 m inverted L, with a substantial length horizontal wire, makes a
> poor 80 meter radiator because of high angles. A T will give you more low
> angle radiation.
>
> 73,
> George,
> AA7JV
>
>
>> On Wed, 19 Feb 2020 15:31:21 -0500
>> "Ed Sawyer" <sawyered@earthlink.net> wrote:
>> Rick said it better. Thanks Rick. The T has been a great performer for me
>> in 4 different locations over the years. I swear by it for 55 - 70 ft
>> vertical sections.
>>
>> Ed N1UR
>>
>> -----Original Message-----
>> From: Richard (Rick) Karlquist [mailto:richard@karlquist.com] Sent:
>> Wednesday, February 19, 2020 3:04 PM
>> To: Ed Sawyer; donovanf@starpower.net; topband@contesting.com
>> Subject: Re: Topband: T-loaded vertical
>>
>>
>>> On 2/19/2020 11:50 AM, Ed Sawyer wrote:
>>> I have personally found that for Ts that are only 70 ft vertical, like
>>> mine, the ground losses of the long topped L are not as desirable as the
>>> cancelled out horizontal lobes of the T. If the T were say 90 ft of
>>> vertical, I don’t think the T adds as much value.
>>> Ed N1UR
>>>
>>>
>> When you model an inverted L, the driving point resistance
>> goes up when you lengthen the top. This it appears that
>> you decreased ground losses and your efficiency goes up.
>> However, if model vertical polarized radiation vs input
>> power, you find that your effective efficiency actually
>> goes down.
>>
>> Extending the inverted L top out to where you have a 1/4
>> wavelength of wire seems very elegant. The antenna
>> reaches resonance at 1830 and you get a low VSWR without
>> using a tuner. If you model that vs a T vertical, there
>> is no comparison. The T wins.
>>
>> Rick N6RK
>>
>> _________________
>> Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
>
> _________________
> Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
_________________
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
|