Why do we always mount our HF Yagi's in the horizontal plane?
Antenna maintenance would be much easier for those of us with tilt
over towers if the antenna were in the horizontal plane when down for
maintenance!

John Ferrell W8CCW

On Jul 12, 2:46 pm, John Ferrell wrote:
Why do we always mount our HF Yagi's in the horizontal plane?
Antenna maintenance would be much easier for those of us with tilt
over towers if the antenna were in the horizontal plane when down for
maintenance!

John Ferrell W8CCW

John, A local guy has his yagi hinged at the top where the downward
pole slips
into a "U " shaped clasp. a
As his foldover comes down the leverage supplied by
the yagi removes the pole from the clasp and the yagi arrives at
ground level in a horizontal position

"John Ferrell" wrote in message
...
Why do we always mount our HF Yagi's in the horizontal plane?
Antenna maintenance would be much easier for those of us with tilt
over towers if the antenna were in the horizontal plane when down for
maintenance!

John Ferrell W8CCW

vertical yagi's work fine... if you can get them far enough away from the
conductive tower and mast either vertically or horizontally... though i do
believe you get better ground reflection from the horizontal polarization.
There is a new product that allows yagis mounted horizontally to
automatically pivot as you tilt over a tower so they stay level with the
ground.

On Sat, 12 Jul 2008 13:42:36 -0700 (PDT), Art Unwin
wrote:

On Jul 12, 2:46 pm, John Ferrell wrote:
Why do we always mount our HF Yagi's in the horizontal plane?
Antenna maintenance would be much easier for those of us with tilt
over towers if the antenna were in the horizontal plane when down for
maintenance!

John Ferrell W8CCW

John, A local guy has his yagi hinged at the top where the downward
pole slips
into a "U " shaped clasp. a
As his foldover comes down the leverage supplied by
the yagi removes the pole from the clasp and the yagi arrives at
ground level in a horizontal position
That is ingenious!
I will have to think through the details but I think I can implement
it. Keeping weight to a minimum is an important factor.

John Ferrell W8CCW

On Sun, 13 Jul 2008 00:04:55 GMT, "Dave" wrote:


"John Ferrell" wrote in message
.. .
Why do we always mount our HF Yagi's in the horizontal plane?
Antenna maintenance would be much easier for those of us with tilt
over towers if the antenna were in the horizontal plane when down for
maintenance!

John Ferrell W8CCW

vertical yagi's work fine... if you can get them far enough away from the
conductive tower and mast either vertically or horizontally... though i do
believe you get better ground reflection from the horizontal polarization.
There is a new product that allows yagis mounted horizontally to
automatically pivot as you tilt over a tower so they stay level with the
ground.


As soon as I get an opportunity I will rotate mine to vertical at
least until I can investigate the possibilities. If you can recall
more details of the new product I am interested.
The scheme offered by Art sounds like my best bet so far.

In the past I have worked from a step ladder with the tower lowered
and tilted as far as possible. I did not forsee that two knee joint
replacements would take away my use of stepladders for a while!

John Ferrell W8CCW

On Sun, 13 Jul 2008 00:04:55 GMT, "Dave" wrote:


"John Ferrell" wrote in message
.. .
Why do we always mount our HF Yagi's in the horizontal plane?
Antenna maintenance would be much easier for those of us with tilt
over towers if the antenna were in the horizontal plane when down for
maintenance!

John Ferrell W8CCW

vertical yagi's work fine...
....

No.

Look at the horizontal and vertical diagrams of a Yagi.
(Talking about a single Yagi, not stacked)

The narrowing of the beam characteristic is only dominant
in the horizontal orientation, the vertical retains about the
characteristic of a single dipole.

So if you tilt a yagi to vertical, it will receive from all
directions, especially the EMF noise in your vicinity.

When horizontally mounted, it will receive of course from
above ( the sky) and from the bottom below your tower
but generally there is less interference than in the whole
360 degrees around you.

Repeat: the vertical yagi diagram is not much better than
that of a single dipole, regardless how many horizontal elements
you add in length of the beam. Try it out of you don't believe,
but listen to the noise you get, not the signals.
Only stacking of yagis can improve the situation.

w.

hwabnig@ .- --- -. dotat wrote in news:i1bj74h45n3u9redkg4qr1oel8k9nhnqt3@
4ax.com:

....
The narrowing of the beam characteristic is only dominant
in the horizontal orientation, the vertical retains about the
characteristic of a single dipole.

That proposition is not born out my models or measurements of real
antennas.

It is true that the E plane and H plane half power beamwidths are
different, but as boom length (gain) is increased, the two approach each
other.

Owen

One of the advantages of a Yagi is its directivity. When mounted
horizontally, its horizontal pattern is quite directional, but the
pattern in the vertical plane is relatively broad -- the vertical
pattern of a typical HF Yagi in the forward direction, in fact, isn't
much different from a single dipole. If you mount the Yagi vertically,
the two patterns swap so the horizontal pattern ends up very much
broader than when mounted vertically.

A vertically mounted Yagi is vertically polarized, and vertically
polarized radiation reacts differently with the ground than horizontally
polarized radiation. So rotating a moderately or very high yagi from
horizontal to vertical will result in loss of low angle radiation unless
your ground is very highly conductive.

These effects can be very easily be seen by modeling.

Roy Lewallen, W7EL

John Ferrell wrote:
Why do we always mount our HF Yagi's in the horizontal plane?
Antenna maintenance would be much easier for those of us with tilt
over towers if the antenna were in the horizontal plane when down for
maintenance!

John Ferrell W8CCW

In message , John Ferrell
writes
Why do we always mount our HF Yagi's in the horizontal plane?
Antenna maintenance would be much easier for those of us with tilt
over towers if the antenna were in the horizontal plane when down for
maintenance!

John Ferrell W8CCW

I read somewhere you get more ground gain with horizontal . Something
to do with Brewster angle.

Brian GM4DIJ

--
Brian Howie

http://www.nn4zz.com/tiltplate.htm

"Dave" wrote in message news:HEbek.91$kf4.54@trnddc03...

"John Ferrell" wrote in message
...
Why do we always mount our HF Yagi's in the horizontal plane?
Antenna maintenance would be much easier for those of us with tilt
over towers if the antenna were in the horizontal plane when down for
maintenance!

John Ferrell W8CCW

vertical yagi's work fine... if you can get them far enough away from the
conductive tower and mast either vertically or horizontally... though i do
believe you get better ground reflection from the horizontal polarization.
There is a new product that allows yagis mounted horizontally to
automatically pivot as you tilt over a tower so they stay level with the
ground.