Topband: low inv-vee

Thu Mar 29 23:31:32 EDT 2018

Guy,
Your's is about as complete an explanation as it gets. I only would like to 
add one aspect (which is covered by the reference to antenna efficiency) but 
is perhaps worth pointing out.
Opinions on vertical vs. horizontal on are strongly subject to one's 
location. In the desert (AZ, etc.) it is very hard to make a vertical 
efficient, and you will probably come to the conclusion that horizontal 
polarization is the best. Near (or over) salt water, you are more likely to 
come to the opposite conclusion.
It is not only the ground near the antenna (which you could somewhat remedy 
with radials), but for up to a mile on TB! In my experience the difference 
can be as much as 10 dB. That is a very different experience.
73,
George,
AA7JV

On Thu, 29 Mar 2018 15:09:56 -0400
  Guy Olinger K2AV <k2av.guy at gmail.com> wrote:
> Yes,  the real world on 160 is very complicated, and by some issues that
> seem, anyway, to be unknown to more hams than not.
>
> W8JI had a 160 dipole up at 300 feet and ran over a year's worth of A/B
> tests, concluding after all that data, that the dipole would never beat a
> commercial-AM-BC-quality vertical and radial field, and only infrequently
> would equal it.
>
> 160 behaves more like the broadcast band than not.
>
> 80 is the transition band to horizontal 40 and up. An 80 4 square is a
> common and satisfactory solution to DX and contest operation, though not
> the ultimate. 8 circle vertical arrays, and such things as catenary
> supported wide spaced 80m four element wire yagis or tower supported two
> element quads seem to be king of the hill, indicating a mix of vertical and
> horizontal killer solutions. By 40m killer vertical solutions are gone.
> People put up fixed wire yagi's on 40 that a 40m four square cannot touch.
>
> Over in northern Europe there was for a while a full size mega-monster full
> sized 3 element 160 horizontal yagi, where the two story house at the
> bottom of the tower looked like a dog house in the picture. Interestingly,
> I never saw rave reviews on that solution. It was so large that
> parachutists would do base-jumping off the end of the boom. In the end,
> regardless of the amazing engineering to get it up in the first place,
> northern winter weather got it.
>
> However one might explain it, or try and quantify it, on 160 meters it is
> clear that generally and on average, **efficient** vertically polarized
> antennas will beat the snot out of **efficient** horizontally polarized
> antennas.
>
> Whether one can manage some degree of QSO-making from a disadvantaged setup
> has to be answered "yes". One only needs favorable propagation path loss
> that can tolerate the degree of RF loss in the disadvantaged antenna
> system.
>
> With vertical polarization on 160, the answer always lies in discerning RF
> loss in the antenna system, or proposed system, including effects of
> environment. Cleaning out all the remediable RF loss issues in a system
> will most likely render a strong performer. A simple mid-sized inverted L
> on 160, **where all the RF loss issues have been cleaned up**, will put one
> in the top 10% of transmitted signals, significantly exceeded only by
> well-done multielement designs, or single element antennas at one of those
> amazing locations.
>
> A phenomenon in 160 contests, which I observe to this day, is that, at a
> decent contest station, 90% of the strong signals will be worked in the
> first third of the contest, often in the first several hundred contacts if
> one starts S&P. After that there will be a handful of midwest and
> east-of-the-Rockies QRP stations I hear, whose signal strengths EXCEED the
> majority of the rest of the stations in the contest.
>
> That leaves one with an inescapable observation, that half or more of 160
> meter antenna systems in use are somehow brutally disadvantaged.
>
> Even if one presumes that the huge percentage of mid-to-late contest QSO's
> are only 100 watts, that still leaves one with the problem that the great
> proportion of those 100 watt signals ARE DISADVANTAGED BY AT LEAST 13 dB RF
> LOSS SOMEWHERE IN THEIR ANTENNA SYSTEM/ENVIRONMENT. They are being exceeded
> by stations running QRP.
>
> While vertical vs horizontal could account for some, there is a large
> collection of anecdotal reports + RBN measurements from remediated stations
> that show such a magnitude of loss is decidedly possible in a vertical
> system.
>
> In this discussion about horizontal vs vertical, one must make sure we pay
> attention to the 1000 pound gorilla in the room: Remediable RF loss in the
> antenna system and environs.
>
> 73, Guy K2AV
> k2av.com
>
> *--------------------------------*
> *Lowering SWR does*
> *   not reliably predict*
> *   better performance.*
>
> *A dummy load, *
> *   with its perfect SWR, *
> *   is a worse antenna *
> *   than a light bulb. *
>
> *First discern and remove *
> *   RF loss in low band*
> *   antenna systems and*
> *   their environments.*
> *----------------------------------*
>
> On Thu, Mar 29, 2018 at 10:11 AM, K4SAV <RadioXX at charter.net> wrote:
>> If you run a NEC analysis it will show that a 160 dipole at a half
>> wavelength height will blow away any vertical when the signal is broadside
>> to the dipole.  The people that have tried this say it aint so.  At least
>> some of the reasons are that NEC knows nothing about 160 propagation and it
>> knows nothing about the effect of Earth's electron gyrofrequency.  That
>> varies a lot depending on where you are located on this earth. Analysis is
>> nice and easy but you have to include everything for it to simulate the
>> real world, and the real world on 160 is very complicated.
>>
>> Jerry, K4SAV
>>
>>
>> On 3/28/2018 9:50 PM, Mark K3MSB wrote:
>>> I don't think so.  In my Electromagnetic Fields and Waves class in EE
>>> school (way back when dinosaurs just stopped roaming the earth and
>>> Constellations still graced the skies...) the prof derived the equation
>>> for
>>> a received signal.  The polarization terms disappeared after the first
>>> ionospheric bounce.
>>>
>>> 73 Mark K3MSB
>>>
>>>
>>> On Wed, Mar 28, 2018, 9:03 PM Steve Maki <lists at oakcom.org> wrote:
>>>
>>> Interesting. Some say that on 160 vertical polarization rules, while on
>>>> 80, horizontal polarization rules (or at least *often* rules). Of course
>>>> polarization and angle of arrival are two different things...
>>>>
>>>> -Steve K8LX
>>>>
>>>> On 03/28/18 17:23 PM, Roger Kennedy wrote:
>>>>
>>>> Well I've said it before and I'll doubtless say it again . . .
>>>>>
>>>>> In my experience, most DX propagation on 160m ISN'T low angle  (unlike
>>>> 80m
>>>>> when it nearly always IS.)
>>>>>
>>>>> For the past 45 years, at several different QTHs I've always used a
>>>>> horizontal co-ax fed halfwave dipole, only 50ft high . . . I'm sure most
>>>>> people would agree I put a respectable DX signal.  I've regularly worked
>>>> all
>>>>> over the world on Top band, and I've never had trouble getting through
>>>>> pile-ups to work Dx-peditions.
>>>>>
>>>>> Plus a dipole at 40 feet will never really be an inverted vee ! (just a
>>>>> horizontal antenna with drooping ends) - You'd have to have the centre
>>>>> at
>>>>> least 100ft high for it to be an inverted vee.
>>>>>
>>>>> Roger G3YRO
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