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
>
>
_______________________________________________
UR RST IS ... ... ..9 QSB QSB - hw? BK
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