Assume there is only one spot on your hilly land that you can pull in
your favorite FM station, 90 Mhz, over the competition, and only with
a horizontal dipole at a certain azimuth. A Yagi doesn't help, as
we are depending fully on the null.

Commercial FM stations are vertically polarized, cause most of the people
that listen are in cars. I have found this to be true in my homebrew antennas
(at least around here). You might try changing the polarization, and see if
that helps.

Not sure why you think a yagi won't help. A 3 or 4 el. yagi with a good F/B
and proper polarization will be a big improvement over the end nulls of a
dipole.

Using great sheets of metal for a dipole will increase the bandwidth, but
that is not what you are looking for. Using the great sheets of metal for a
screen reflector, or corner reflector could produce some big improvements.

73 Gary N4AST

"JGBOYLES" wrote in message
...
Assume there is only one spot on your hilly land that you can pull in
your favorite FM station, 90 Mhz, over the competition, and only with
a horizontal dipole at a certain azimuth. A Yagi doesn't help, as
we are depending fully on the null.

Commercial FM stations are vertically polarized, cause most of the
people
that listen are in cars.


I thought the FCC required equal EIRP of both vertical AND horizontal
polarization for an FM broadcast station? Did the horizontal requirement get
deleted?

Ed
wb6wsn

I thought the FCC required equal EIRP of both vertical AND horizontal
polarization for an FM broadcast station? Did the horizontal requirement get
deleted?

I don't know, just reporting on the results of my tinkering, I get by far the
best signal with vertical polarization. I assumed that was becuse they wanted
to target automobiles. Maybe the EIPR of the stations in both the vertical
and horizontal planes in my area are not in compliance?
73 Gary N4AST

Most of the FM stations broadcast circular polarization, but it seems
that more of the hoz part gets attenuated by trees more than vertical.
So if there is a shallow angle to the transmitter, through some vegetation
Vert seems more dominant.

But I think this changes with over-the-horizon, and it gets more Hoz,
but I have not measured this.

On the original question, you can add antenna patterns if they are phased
right.
You can put a piece of metal in the direct path to block signal, may go down
10 dB or so.
Metal could be screen wire mesh between dipole and unwanted transmitter 10
by 10,
centered to get phase null in the back.



"JGBOYLES" wrote in message
...
I thought the FCC required equal EIRP of both vertical AND horizontal
polarization for an FM broadcast station? Did the horizontal requirement
get
deleted?

I don't know, just reporting on the results of my tinkering, I get by far
the
best signal with vertical polarization. I assumed that was becuse they
wanted
to target automobiles. Maybe the EIPR of the stations in both the
vertical
and horizontal planes in my area are not in compliance?
73 Gary N4AST

I used to live on the very fringe of an FM stations coverage area, probably
outside their intended cover area. Had great succes with 4 stacked 2 element
Yagis(think of old TV antennas). I and a guy down the street who had a
hundred foot tower were the only people in the county who could get the
station reliably. This was pretty good since this was the only FM station
that serviced the area at that time.


"JGBOYLES" wrote in message
...
Assume there is only one spot on your hilly land that you can pull in
your favorite FM station, 90 Mhz, over the competition, and only with
a horizontal dipole at a certain azimuth. A Yagi doesn't help, as
we are depending fully on the null.

Commercial FM stations are vertically polarized, cause most of the
people
that listen are in cars. I have found this to be true in my homebrew
antennas
(at least around here). You might try changing the polarization, and see
if
that helps.

Not sure why you think a yagi won't help. A 3 or 4 el. yagi with a good
F/B
and proper polarization will be a big improvement over the end nulls of a
dipole.

Using great sheets of metal for a dipole will increase the bandwidth,
but
that is not what you are looking for. Using the great sheets of metal for
a
screen reflector, or corner reflector could produce some big improvements.

73 Gary N4AST