This is as perfect an answer as any expert could come up with!!!! :-)
I've been a ham for over 42 years. But well before I was the
wet-behind-the-ears Novice-class WN8BTU, many experienced Topbanders have
found that *all especially successful 160m DX stations use vertical
polarization. That's just a fact.*
>From http://www.w0btu.com/160_meters.html. Comments from W8JI himself.:
"Nearly all especially successful stations on 160 use a vertically
polarized antenna of some type for transmitting. That's just a fact."
"The fact is....... an Inverted L with 20 or more radials at least 50 feet
and hopefully 100 feet long will absolutely smoke any normal height loop
antenna or dipole antenna at nearly any distance on 160 meters. The
possible exception is between 20 and 200 miles."
"I have a full size 160 dipole at 300 feet, and it is never really much
better than a 1/4 wave vertical at any distance in any direction. As a
matter of fact, the dipole is 10-20 dB weaker than the vertical off the
dipole ends. The dipole only beats the vertical broadside to the dipole,
and then only rarely!! And this is with the dipole 300 feet above ground."
Some other profound comments by W8JI about "what is a good antenna" from
various online forums:
"Asking a group about the best antenna, or what works, is like asking a
group what kind of religion is good, or what kind of woman to pick. In a
large unrestricted group some would tell you Satanism is the best religion
and boys make the best wives. The same is true with antennas.
"I'd bet over 90% of Hams don't even really know how or why an antenna
works or how to tell if it works. Most opinions are really based only on if
the antenna makes contacts and accepts power. This is why so many antennas
are able to be sold with totally false claims, and it has been that way for
years. Claims that are utter nonsense are widely absorbed as fact by
significant cross sections of the population.
"Probably the single largest truth is almost ANY antenna will make someone
happy as can be, so long as it works any amount at all. People find
something they seem to like, if it is based on bad science or outright lies
they get into a herd of sheep who believe the same way, and you have a cult
following that reinforces each other in their beliefs no matter how
unsubstantiated or false they are."
http://forums.qrz.com/index.php?threads/best-option-for-an-antenna.291026/page-2
http://www.w0btu.com/160_meters.html
I sort of doubt that Tom (or other experts who have left this Reflector)
will be inclined to chime in here (which is fine), but his experiments and
experience are peerless.
My own meager experience has proved this.
Maybe the problem here is that we haven't defined DX. To me, DX is from my
QTH in SW Missouri to Africa, Asia, Oceania, etc.; and *not* just a few
hundred miles.
73, Mike
www.w0btu.com
On Thu, Mar 29, 2018 at 2:09 PM, Guy Olinger K2AV <k2av.guy@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.
>
> ...
>
> 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.*
> *----------------------------------*
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