Looking for a site or information on incoming
radiation angles specifically for 160 metres.

1 How is it measured ?
1a Can it discriminate between vertical and horizontal
or what ever polarisation

2 What is the angles per percentage of contacts

3 Are they all horizontally polarised when subject to skip?
for distances over say 1000 miles distance

One well known DXer (Tom) stated on this
newsgroup that a horizontal dipole at 1/2 wave
length was inferior to his other antennas, but
no specifics given!

Appreciate any pointers on the above.
Happy New Year
Art

On 31 Dec 2003 12:33:11 -0800, (Art Unwin KB9MZ)
wrote:

Looking for a site or information on incoming
radiation angles specifically for 160 metres.

0° with respect to the horizon.


1 How is it measured ?

You could use a spirit level.

1a Can it discriminate between vertical and horizontal
or what ever polarisation

Spirit levels usually only work one way, for an angle relative to
tangential to earth's surface.

2 What is the angles per percentage of contacts

Vertical/useful

Conduct your own poll. How many remote BCB's can you copy for each?

3 Are they all horizontally polarised when subject to skip?
for distances over say 1000 miles distance

160M skip? Perform poll above.


One well known DXer (Tom) stated on this
newsgroup that a horizontal dipole at 1/2 wave
length was inferior to his other antennas, but
no specifics given!

He was being generous.

Appreciate any pointers on the above.

Think local, act global.

Happy New Year
Art

73's & Season's Groanings,
Richard Clark, KB7QHC

In message , Art Unwin
KB9MZ writes
Looking for a site or information on incoming
radiation angles specifically for 160 metres.

1 How is it measured ?

The same way it was measured in the 20's for B/C reception. Two
separated antennas at different heights feeding an oscilloscope to
produce an ellipse. The phase difference between the antennas allows the
angle to be calculated.

Mike

--
M.J.Powell

Art, K9MZ wrote:
"---radiation angles specifically for 160 meters.
1. How is it measured?"

In degrees above the horizon. It`s geometrical. The effective height of
the reflecting layer above the earth has been observed for a long time
and can be predicted with some accuracy, based upon location, time,
solar radiation, etc.

The angle of incidence is equal to the angle of reflection to a
reference normal to the reflecting plane. So, low angles serve for long
distances between stations, and high angles for short distances that are
too distant to be reached by the groundwave.

Capt. Paul H. Lee, USNR, K6TS has a chart of degrees above the horizon
versus distance to the first reflection zone (a single hop) on page 11
of "Vertical Antenna Handbook", a "CQ" publication. As the height of the
latyer is variable, this is an approximation based on probabilities.

A 5/8-wave vertical gives optimum low-angle radiation between 3 and 27
degrees. The latter angle gets you out to about 500 miles. Lower angles
get you out to about 2000 miles on one hop.

Vertical antennas work with vertically polarized waves. Once the wave is
reflected by the ionosphere, polarization of the reflection is more or
less random.

"2. What is the angles per percentage of contacts?"

Depends on where your station is in respect to the majority of stations
you want to contact.

"3. Are they all horizontally polarized when subject to skip?"

No. The ionosphere does not care what the wave polarization is. It will
reflect whatever strikes it at various polarizations. It won`t maintain
polarizations! You can receive via the ionosphere almost equally well,
on average, with any polarization regardless of what was transmitted.
Noise reception is likely worse using a vertical receiving antenna.

"Tom stated on this newsgroup that a horizontal dipole at 1/2-wavelength
was inferior to his other antennas---."

Can`t argue with Tom`s observation about his antennas, but it does not
correspond with most observations of horizontal antenna performance when
you have a resonant dipole at 1/2-wave above the earth. Look at Fig 12-D
on page 3-11 of the 19th edition of the ARRL Antenna Book. Maximum
radiation is at 30-degrees above the horizon. From Capt. Lee`s diagram,
that would get you stations as close as 500 miles, and beyond 1000 miles
due to the range of strong elevation angles in the pattern.

I don`t know what Ton`s problems are but suspect that he ignores some of
the ground effects. He has expressed dissatisfaction with his verticals
too.

Vertivcals in particular are sensitive to good earth under and around
the antenna.

Horizontal polarization isn`t bad for HF. Most of the world`s HF
commercial stations use horizontal antennas for skywave propagation.

Best regards, Richard Harrison, KB5WZI

"Richard Harrison" wrote in message
...
Art, K9MZ wrote:
"---radiation angles specifically for 160 meters.
1. How is it measured?"

In degrees above the horizon. It`s geometrical. The effective height of
the reflecting layer above the earth has been observed for a long time
and can be predicted with some accuracy, based upon location, time,
solar radiation, etc.

Where can I see these predictions for the present time?

The angle of incidence is equal to the angle of reflection to a
reference normal to the reflecting plane. So, low angles serve for long
distances between stations, and high angles for short distances that are
too distant to be reached by the groundwave.

Understood


Capt. Paul H. Lee, USNR, K6TS has a chart of degrees above the horizon
versus distance to the first reflection zone (a single hop) on page 11
of "Vertical Antenna Handbook", a "CQ" publication. As the height of the
latyer is variable, this is an approximation based on probabilities.

I will pull that one out.


A 5/8-wave vertical gives optimum low-angle radiation between 3 and 27
degrees. The latter angle gets you out to about 500 miles. Lower angles
get you out to about 2000 miles on one hop.

O.K.

Vertical antennas work with vertically polarized waves. Once the wave is
reflected by the ionosphere, polarization of the reflection is more or
less random.

Hmm, so a vertical tho low angle would miss out on horizontal polarisations
which leaves a lot of unknown with respect to best antenna for Top band

"2. What is the angles per percentage of contacts?"

Depends on where your station is in respect to the majority of stations
you want to contact.

Over 1000 miles

"3. Are they all horizontally polarized when subject to skip?"

No. The ionosphere does not care what the wave polarization is. It will
reflect whatever strikes it at various polarizations. It won`t maintain
polarizations! You can receive via the ionosphere almost equally well,
on average, with any polarization regardless of what was transmitted.

Well I thought that kmost transmitions changed to horizontal after
reflection!

Noise reception is likely worse using a vertical receiving antenna.

Well I am confused about that
My present rotatable dipole at a 'low" height matches a beverage at 15
degrees but unfortunately the gain continues to a max at 90 degrees where as
the beverage
whereas the beverage nulls out the higher angles which ius why I presume it
was chosen as a listening antenna.


"Tom stated on this newsgroup that a horizontal dipole at 1/2-wavelength
was inferior to his other antennas---."

Can`t argue with Tom`s observation about his antennas, but it does not
correspond with most observations of horizontal antenna performance when
you have a resonant dipole at 1/2-wave above the earth. Look at Fig 12-D
on page 3-11 of the 19th edition of the ARRL Antenna Book. Maximum
radiation is at 30-degrees above the horizon. From Capt. Lee`s diagram,
that would get you stations as close as 500 miles, and beyond 1000 miles
due to the range of strong elevation angles in the pattern.

I don`t know what Ton`s problems are but suspect that he ignores some of
the ground effects. He has expressed dissatisfaction with his verticals
too.

Vertivcals in particular are sensitive to good earth under and around
the antenna.

Horizontal polarization isn`t bad for HF. Most of the world`s HF
commercial stations use horizontal antennas for skywave propagation.

Well I have put my dipole in the vertical position also which negates use of
radials but I have not noticed any profound differences as yet after a few
days !

This new band to me is raising a lot of questions
for me that I haven't thought of before so I am at a new horizon and without
the spirit level as the bubble has burst.
Cheers
Art

band
Best regards, Richard Harrison, KB5WZI

AArt, KB9MZ wrote:
"Where can I see these predictions for the present time?"

Inquire of the National Institute of Science and Technology for
propagation forecasts. (Your tax dollars at work) The National Bureau of
Standards used to broadcast a limited amount of propagation forecasts on
WWV. Haven`t listened in a long time, so don`t know what`s on WWV now.
NBS also made available extensive propagation forecast information for
the world, by mail, on a subscriotion basis.

Best regards, Richard Harrison, KB5WZI

(Richard Harrison) wrote in message

"Tom stated on this newsgroup that a horizontal dipole at 1/2-wavelength
was inferior to his other antennas---."

Can`t argue with Tom`s observation about his antennas, but it does not
correspond with most observations of horizontal antenna performance when
you have a resonant dipole at 1/2-wave above the earth. Look at Fig 12-D
on page 3-11 of the 19th edition of the ARRL Antenna Book. Maximum
radiation is at 30-degrees above the horizon. From Capt. Lee`s diagram,
that would get you stations as close as 500 miles, and beyond 1000 miles
due to the range of strong elevation angles in the pattern.

I think what Tom is referring to is transmitting. It's quite normal
for a good vertical to beat a dipole on the lower bands regardless of
theory. Even if the dipole is at 1/2 wave up. Heck, I saw this as high
as 40m. My dipole on that band never beat my vertical at night on
longer paths. Tom uses separate antennas for receiving. IE: beverages,
phased short verticals. His transmit verticals are tall towers. Late
at night, my 40m mobile vertical beats my home dipole that is at 40 ft
to any path over 800 miles. My full size 40m elevated ground plane
would thoughly trounce the dipole big time by 2-4 S units depending on
the length of the path. For DX transmitting on the lower bands,
vertical polarization is the best way to go. I'm thoughly convinced of
that by many tests over time. Some mine, some other people like Tom.
MK

Mark Keith wrote:
"For DX transmitting on the lower bands, vertical polarization is the
best way to go."

In some cases. If that were always the case, why do commercial shortwave
stations all use horizontal polarization for both point-to-point service
and broadcasting?

During my years in shortwave broadcasting, I never saw a single
vertically polarized antenna used for HF transmitting.

My experience is not unique. E.A. Laport was Chief Engineer, RCA
International Division of Radio Corporation of America (RCA). For many
years RCA was the largest short-wave communications organization in the
world. In his book, "Radio Antenna Engineering", Ed Laport says:

"The earliest high-frequency beam antennas used vertical polarization,
but subsequent evolution has caused the almost universal use of
horizontal polarization. There may be a reversion to vertical
polarization in the future for certain applications."

It was natural to try vertical polarization first for directional arrays
as low and medium frequencies were first exploited for radio and these
had to use vertical antennas. It was uneconomical to elevate horizontal
antennas to heights necessary for sky wave performance and there is no
ground wave propagation of horizontally polarized waves. The directional
vertical antenna had been developed early in broadcasting by Brown,
Lewis, and Epstein who did their RCA development work at HF for economy
and convenience. Work was already in place for the earliest vertical HF
beam antennas. These only evolved into the universal horizontal
polarization at HF due to real advantages.

Huge investments are made in HF transmitting antenna farms. I worked in
a station that had a farm of over 400 acres of HF antennas, all
horizontally polarized. This was no flip of a coin decision. The
decision was based on the preponderance of experience at the time. Our
paths were so long that we had to consider 2-hops in addition to a
single hop on most.

There surely must be instances where vertical polarization proves better
than horizontal, but these are exceptions, not the rule.

An example might be an antenna closely surrounded by the sea. A vertical
array should be ideal.

Best regards, Richard Harrison, KB5WZI

Richard Harrison wrote:
There surely must be instances where vertical polarization proves better
than horizontal, but these are exceptions, not the rule.

Vertically polarized noise is about 10 dB higher than horizontally
polarized noise at my QTH rendering a vertical antenna virtually
useless for receiving compared to a horizontal antenna.
--
73, Cecil http://www.qsl.net/w5dxp



-----= Posted via Newsfeeds.Com, Uncensored Usenet News =-----
http://www.newsfeeds.com - The #1 Newsgroup Service in the World!
-----== Over 100,000 Newsgroups - 19 Different Servers! =-----

Cecil Moore wrote:

Richard Harrison wrote:

There surely must be instances where vertical polarization proves better
than horizontal, but these are exceptions, not the rule.

Vertically polarized noise is about 10 dB higher than horizontally
polarized noise at my QTH rendering a vertical antenna virtually
useless for receiving compared to a horizontal antenna.

Sorry, forgot to say this was on 40m.
--
73, Cecil http://www.qsl.net/w5dxp



-----= Posted via Newsfeeds.Com, Uncensored Usenet News =-----
http://www.newsfeeds.com - The #1 Newsgroup Service in the World!
-----== Over 100,000 Newsgroups - 19 Different Servers! =-----