Effects of TOA
 

While operating on 10M I have observed that a halfwave vertical dipole
will communicate to different areas than a 1.25wl vertical monopole an
example would be that during a band opening the 1/2 wl antenna may be
working predominantly into New York while the 1.25 wl antenna is
working best in California or was it vice versa. This has proven
useful for me, instead of fighting a pile-up and can just talk
somewhere else. The two verticals may soon be replaced with a tri-
bander and I was wondering if I could get this same type of effect by
tilting the antenna vertically(no change in polarity) with a remote
controlled device. I think it would be pretty cool to hear different
areas of the country pop in and out as the elevation of the antenna is
changed.

Jimmie

Effects of TOA
 

"JIMMIE" wrote in message
oups.com...
While operating on 10M I have observed that a halfwave vertical dipole
will communicate to different areas than a 1.25wl vertical monopole an
example would be that during a band opening the 1/2 wl antenna may be
working predominantly into New York while the 1.25 wl antenna is
working best in California or was it vice versa. This has proven
useful for me, instead of fighting a pile-up and can just talk
somewhere else. The two verticals may soon be replaced with a tri-
bander and I was wondering if I could get this same type of effect by
tilting the antenna vertically(no change in polarity) with a remote
controlled device. I think it would be pretty cool to hear different
areas of the country pop in and out as the elevation of the antenna is
changed.

It would work, theoretically, for a small change but I doubt you'd ever
notice the effect.

You need a very directional (many elements) antenna to see a big difference
in the amount of signal in the elevation plane. High gain UHF TV antennas
do have tilters, but it's to match the angle of arrival of the signal, which
may be coming out of a duct or reflected off a nearby ridge. See a sample
at http://www.atechfabrication.com/prod...omy_tilter.htm

Most tribanders are three elements and have a 3dB beamwidth of about 60
degreees in the azimuth (plan view) plane -- worse in the elevation plane.

Further complication: The ground affects the shape of the elevation
pattern, maybe more than any tilt you could apply. You might better
fine-tune the angle of arrival by cranking a tower section up and down.

"Sal"

Effects of TOA
 

"Sal M. Onella" wrote in message
...

"JIMMIE" wrote in message
oups.com...
While operating on 10M I have observed that a halfwave vertical dipole
will communicate to different areas than a 1.25wl vertical monopole an
example would be that during a band opening the 1/2 wl antenna may be
working predominantly into New York while the 1.25 wl antenna is
working best in California or was it vice versa. This has proven
useful for me, instead of fighting a pile-up and can just talk
somewhere else. The two verticals may soon be replaced with a tri-
bander and I was wondering if I could get this same type of effect by
tilting the antenna vertically(no change in polarity) with a remote
controlled device. I think it would be pretty cool to hear different
areas of the country pop in and out as the elevation of the antenna is
changed.

It would work, theoretically, for a small change but I doubt you'd ever
notice the effect.

You need a very directional (many elements) antenna to see a big
difference
in the amount of signal in the elevation plane. High gain UHF TV antennas
do have tilters, but it's to match the angle of arrival of the signal,
which
may be coming out of a duct or reflected off a nearby ridge. See a sample
at http://www.atechfabrication.com/prod...omy_tilter.htm

Most tribanders are three elements and have a 3dB beamwidth of about 60
degreees in the azimuth (plan view) plane -- worse in the elevation plane.

Further complication: The ground affects the shape of the elevation
pattern, maybe more than any tilt you could apply. You might better
fine-tune the angle of arrival by cranking a tower section up and down.

"Sal"



Thats really what I thought to, I dont think it would be practical to
implament with a yagi. I have too also admit the extreme variations I
reported while using the verticals is pretty rare and I made them sound more
common than they reallly are.

Jimmie

Effects of TOA
 

"Jimmie D" wrote
While operating on 10M I have observed that a halfwave vertical dipole
will communicate to different areas than a 1.25wl vertical monopole an
example would be that during a band opening the 1/2 wl antenna may be
working predominantly into New York while the 1.25 wl antenna is
working best in California or was it vice versa. This has proven
useful for me, instead of fighting a pile-up and can just talk
somewhere else. The two verticals may soon be replaced with a tri-
bander and I was wondering if I could get this same type of effect by
tilting the antenna vertically(no change in polarity) with a remote
controlled device. I think it would be pretty cool to hear different
areas of the country pop in and out as the elevation of the antenna is
changed.

I don't know how you missed it, but there have been several threads
here recently about TOA, tilting antenna elements, purity of polarity,
ect...A google search on Art Unwin will provide more than you'll
ever want to know, especially about mental health and junk science.
The demo version of EZNEC should also provide you with plenty
of useful answers, and will sink enough of your time to keep you off
the streets and out of the bars!Several programs will allow you to
model effects of changing antenna heights ( only one of a multitude of
variables) on the resulting signal path.
Keep us here on RRAA posted on your results, and gud luck in
the contests!

Mike W5CHR

Effects of TOA
 

On 13 Apr 2007 16:41:25 -0700, "JIMMIE"
wrote:

I have observed that a halfwave vertical dipole
will communicate to different areas than a 1.25wl vertical monopole

Hi Jimmie,

A low halfwave operates best at 16 degrees; a quarterwave works best
in the 20s of degrees; while a 1.25 wavelength antenna works best in
the high 50s of degrees.

This presumes the last two are both ground mounted. Given that any of
these presumptions are at best a guess, then the numbers are merely
for guidance as reality may be vastly different (you really haven't
given us enough information). Actual physical size and elevation help
considerably. Also, as this is 10M, was some of the traffic from the
neighborhood (within 20 miles)?

73's
Richard Clark, KB7QHC

Effects of TOA
 

I don't know about verticals vs. beams, but certainly you can hear different
areas when using a vertical or using a dipole. I've used both during
numerous contests and found that from NC a dipole hears the Caribbean while
a vertical hears Argentina, Brazil and points south. This is a G5RV at
about 30 feet.

The beams hearing ability may wash out this difference, but the "incoming"
polarity has nothing to do with the "transmitted" polarity. This is why I
have both available.

Good luck,

Bill, W4WNT


"JIMMIE" wrote in message
oups.com...
While operating on 10M I have observed that a halfwave vertical dipole
will communicate to different areas than a 1.25wl vertical monopole an
example would be that during a band opening the 1/2 wl antenna may be
working predominantly into New York while the 1.25 wl antenna is
working best in California or was it vice versa. This has proven
useful for me, instead of fighting a pile-up and can just talk
somewhere else. The two verticals may soon be replaced with a tri-
bander and I was wondering if I could get this same type of effect by
tilting the antenna vertically(no change in polarity) with a remote
controlled device. I think it would be pretty cool to hear different
areas of the country pop in and out as the elevation of the antenna is
changed.

Jimmie

Effects of TOA
 

"Richard Clark" wrote in message
...
On 13 Apr 2007 16:41:25 -0700, "JIMMIE"
wrote:

I have observed that a halfwave vertical dipole
will communicate to different areas than a 1.25wl vertical monopole

Hi Jimmie,

A low halfwave operates best at 16 degrees; a quarterwave works best
in the 20s of degrees; while a 1.25 wavelength antenna works best in
the high 50s of degrees.

This presumes the last two are both ground mounted. Given that any of
these presumptions are at best a guess, then the numbers are merely
for guidance as reality may be vastly different (you really haven't
given us enough information). Actual physical size and elevation help
considerably. Also, as this is 10M, was some of the traffic from the
neighborhood (within 20 miles)?

73's
Richard Clark, KB7QHC

These are ground mounted monopoles and I am only talking about
skip reception. The antennas were mounted on the ground in an attempt to
eliminate as much local reception as possible. I am not too interested in
the local 10M chatter.not that there is very much but have noticed that the
two antennas talk into completely different areas on occasion. I first
noticed the phenmena back in the late sixties when I bult a 1.25 wl antena
for 11m believing that longer was always better. It was an interesting
antenna sometimes allowing me to work into canada from S Ga even when
others in the area werent even experiencing skip conditions. I was about 16
at the time but I do seem to remember that hering an opening on this antenna
meant that an opening would soon happen for the area. I was wondering if I
could duplcate the effect by tilting a yagi to a high angle. The more I
think about it I dont belive this would not be practical even if it was
possible. Not only would I have to have the antenna tipped at the right time
I would also have to have it pointed in the right direction. I would be
interested in knowing if others have experienced this effect using unually
long vertical antennas on the higher frequencies.

Effects of TOA
 

Thanks , sounds about like what I have been experiencing. The time I heard
the guys in California the band was stone quite and when I switched
antennas it was still quite except for the stations in New York Weird
feeling.

Jimmie


"W4WNT" wrote in message
...
I don't know about verticals vs. beams, but certainly you can hear
different areas when using a vertical or using a dipole. I've used both
during numerous contests and found that from NC a dipole hears the
Caribbean while a vertical hears Argentina, Brazil and points south. This
is a G5RV at about 30 feet.

The beams hearing ability may wash out this difference, but the "incoming"
polarity has nothing to do with the "transmitted" polarity. This is why I
have both available.

Good luck,

Bill, W4WNT


"JIMMIE" wrote in message
oups.com...
While operating on 10M I have observed that a halfwave vertical dipole
will communicate to different areas than a 1.25wl vertical monopole an
example would be that during a band opening the 1/2 wl antenna may be
working predominantly into New York while the 1.25 wl antenna is
working best in California or was it vice versa. This has proven
useful for me, instead of fighting a pile-up and can just talk
somewhere else. The two verticals may soon be replaced with a tri-
bander and I was wondering if I could get this same type of effect by
tilting the antenna vertically(no change in polarity) with a remote
controlled device. I think it would be pretty cool to hear different
areas of the country pop in and out as the elevation of the antenna is
changed.

Jimmie

Effects of TOA
 

On Sun, 15 Apr 2007 18:43:12 -0400, "Jimmie D"
wrote:

I would be
interested in knowing if others have experienced this effect using unually
long vertical antennas on the higher frequencies.

Hi Jimmie,

Sure, and on 10M too. Unfortunately I was the deaf one when others
were working the skip. It cuts both ways.

73's
Richard Clark, KB7QHC

Effects of TOA
 

"Richard Clark" wrote in message
...
On Sun, 15 Apr 2007 18:43:12 -0400, "Jimmie D"
wrote:

I would be
interested in knowing if others have experienced this effect using unually
long vertical antennas on the higher frequencies.

Hi Jimmie,

Sure, and on 10M too. Unfortunately I was the deaf one when others
were working the skip. It cuts both ways.

73's
Richard Clark, KB7QHC

Yeah the 1.25wl vertical want even put a signal across town on most days,
it is definatly a specialty antenna.

Jimmie