What does Eznec say about the lobe powers?
>From the comments of many using a generic L with dimensions all over the map
it seems that high angle does a lot of good as many are amazed how well it
works especially when an optimum ground is impossible to install.
A good friend was reluctant to try an L 2 years ago due to the many negative
comments. I urged him to try with just his mediocre 80M radials tied in and
he quickly began knocking off DX with ease. Eznec said he had that high
lobe.
The one thing about verticals in particular is that no 2 work alike unless
they are built identical over identical ground and topography.
I wish some would understand this and quit trying to use their own antenna
as the "golden sample benchmark" as we used to say in R&D.
YMMV
Carl
KM1H
----- Original Message -----
From: "Merv Schweigert" <k9fd@flex.com>
To: <topband@contesting.com>
Sent: Monday, October 17, 2011 2:26 PM
Subject: Re: Topband: high take-off angle
>I agree that some high angle may be the optimum at some situation, but
> getting all angles from one
> antenna I cant see as the answer, you are putting power into all the
> different angle
> and no real power into any one of them. So separate antennas would
> seem to
> be the answer. If your putting power into the higher angles of an InvL
> you are not
> putting max power into the lower angles when needed.
>
> I am the station on Molokai that K4XS mentioned, and I do not run a BC
> tower, I have
> a 75 foot vertical with a T top, two sloping wires off the top. but I
> have a BC station
> ground system, 120 - 300 ft plus radials and 120 - 60 ft radials, so
> by theory an
> excellent ground. I can hear far more than it will work, so does it
> work well?
> I think it should be better, but I am limited to what I can obtain for
> materials and
> help to put something up.
> Being right on the beach is a tremendous advantage, modeling will show
> the gain increase
> for that. I am located about a mile from the water, good for a take
> off angle but suffers
> at least minus 3 db from someone right at the salt water edge.
>
> I have a low dipole also, and so far have never seen signals on it
> better than on the
> vertical, no matter what time of day or night, I am sure other
> locations will vary
> on the angle, but so far the lower the better is what I find.
> Im sure your mileage may vary.
> 73 Merv K9FD/KH6
>
>> My point was that with one antenna you could have both angles available.
>> The
>> important thing is having the other station hear you and if you cover a
>> wider range of angles you automatically have better odds.
>>
>> There is nothing that says the path is 100% reciprocal so what you hear
>> may
>> be quite different at the other end.
>>
>> Carl
>> KM1H
>>
>>
>> ----- Original Message -----
>> From: "Dave Mueller"<daven2nl@gmail.com>
>> To:<topband@contesting.com>
>> Sent: Sunday, October 16, 2011 8:14 PM
>> Subject: Re: Topband: high take-off angle
>>
>>
>>
>>> When designing a low band antenna for my Guam QTH, I purposely went
>>> through great trouble to make a true "TEE" vertical to avoid having an
>>> inverted L on 160. I figured that being limited to 55ft of vertical
>>> height, the rest of the "L" would present a significant higher angle
>>> horizontally polarized component. I am located 1,500 miles from Japan
>>> and 7,000 miles from both Eastern North America and Western Europe. I
>>> wanted to maximize low angle takeoff and efficiency by using top loading
>>> and a good radial field, and to keep the radiating portion centered as
>>> much as possible over my radials.
>>>
>>> I understand that high angle propagation does occur on 160m, however low
>>> angle generally rules. With room for only one transmit antenna, I felt
>>> it was more important to be prepared for the 90% scenario, instead of
>>> those rare occasions when high angle takeoff is a factor. I think those
>>> who worked me for a new one and those who still need Guam on 160m will
>>> thank me for the decision I made. By all means, if you have room for
>>> more than one antenna, a second high angle radiator could be the trick
>>> to completing some QSOs. However, if you only have room for one, I'd
>>> aim to have a radiator as high in efficiency with as low an angle of
>>> takeoff as possible. This is what you get with a vertical over salt
>>> water, usually considered "the ideal situation".
>>>
>>> 73, Dave KH2/N2NL
>>>
>>> _______________________________________________
>>> UR RST IS ... ... ..9 QSB QSB - hw? BK
>>>
>>>
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>>>
>> _______________________________________________
>> UR RST IS ... ... ..9 QSB QSB - hw? BK
>>
>>
>
> _______________________________________________
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