I was recently corresponding with an individual regarding reefing points
and sent him a back-lit photo of the sails. While I was looking at it, I
realized how much the whip SSB antenna is tilted backwards (about 10
degrees), and was wondering what effect that tilt would have.

http://www.geoffschultz.org/FreedomY...419_084022.jpg

I regularly use the SSB for e-mail via SailMail, with no problems. When I'm
in the NW Caribbean, I'm a network controller and/or a weather guy for the
NW Caribbean Net (which covers from Panama to the Gulf of Mexico), and
people have always commented what a strong signal I have.

The tilt is due to the stand-off from the rail. I'm wondering if I'd have a
better signal if I were to put a block at the base and make it vertical?

-- Geoff
www.GeoffSchultz.org

"Geoff Schultz" wrote in message
.. .
I was recently corresponding with an individual regarding reefing points
and sent him a back-lit photo of the sails. While I was looking at it, I
realized how much the whip SSB antenna is tilted backwards (about 10
degrees), and was wondering what effect that tilt would have.

Next to nothing. Watch this radiation pattern of a monopole on a ground
plane:
http://www.kyes.com/antenna/navy/rpatterns/antena01.gif

Meindert
PE1GRV

On Wed, 10 Jun 2009 06:00:40 -0500, Geoff Schultz
wrote:

I was recently corresponding with an individual regarding reefing points
and sent him a back-lit photo of the sails. While I was looking at it, I
realized how much the whip SSB antenna is tilted backwards (about 10
degrees), and was wondering what effect that tilt would have.

http://www.geoffschultz.org/FreedomY...419_084022.jpg

I regularly use the SSB for e-mail via SailMail, with no problems. When I'm
in the NW Caribbean, I'm a network controller and/or a weather guy for the
NW Caribbean Net (which covers from Panama to the Gulf of Mexico), and
people have always commented what a strong signal I have.

The tilt is due to the stand-off from the rail. I'm wondering if I'd have a
better signal if I were to put a block at the base and make it vertical?

-- Geoff
www.GeoffSchultz.org


Lot of folks use an insulated backstay for an antenna...

Cheers,

Bruce
(bruceinbangkokatgmaildotcom)

In article ,
Geoff Schultz wrote:

I was recently corresponding with an individual regarding reefing points
and sent him a back-lit photo of the sails. While I was looking at it, I
realized how much the whip SSB antenna is tilted backwards (about 10
degrees), and was wondering what effect that tilt would have.

http://www.geoffschultz.org/FreedomY...419_084022.jpg

I regularly use the SSB for e-mail via SailMail, with no problems. When I'm
in the NW Caribbean, I'm a network controller and/or a weather guy for the
NW Caribbean Net (which covers from Panama to the Gulf of Mexico), and
people have always commented what a strong signal I have.

The tilt is due to the stand-off from the rail. I'm wondering if I'd have a
better signal if I were to put a block at the base and make it vertical?

-- Geoff
www.GeoffSchultz.org

At MF/HF Frequencies, Polarization effects are not a significant
influence in signal strength, or propagation, of EM Emissions,
mainly due to Polarization shifts that happen in the Ionosphere.
Certainly 10 degrees of vertical would even show up at the receiving end
of an MF/HF Link. Wavelengths are just to long at these frequencies to
have polarization be a problem. Some of the best MF/HF Marine
Installations I ever worked on, were 75+ Ft End Feed Wire Antennas,
tuned with a Channelized Antenna Tuner, for the specific Marine Channel
in use, and using the Steel Hull of the ship, for RF Grounding. The RF
Ground of the vessel will be have at least an "Order of Magnitude" more
significance, than the Polarization of the Antenna. Build your self the
BEST POSSIBLE RF Ground you can, and you'll be the Loudest Station on
the Channels, Hands Down......

--
Bruce in alaska
add path after fast to reply

Geoff Schultz wrote in
:

The tilt is due to the stand-off from the rail. I'm wondering if I'd
have a better signal if I were to put a block at the base and make it
vertical?



Not much at all. 90% of your signal is being coupled into that stack of
metal stuff right above the flag, instead of going out on the air,
anyways....

That's where your signal's going........to ground.



--
-----
Larry

If a man goes way out into the woods all alone and says something,
is it still wrong, even though no woman hears him?

"Meindert Sprang" wrote in news:4a2f93d5$0
:

Meindert
PE1GRV



Never saw your call before, Meindert.

73 DE W4CSC, Charleston, South Carolina, USA....



--
-----
Larry

If a man goes way out into the woods all alone and says something,
is it still wrong, even though no woman hears him?

Bruce in alaska wrote in news:fast-CAC4C1.12584110062009
@unknown.usenetserver.com:

Build your self the
BEST POSSIBLE RF Ground you can, and you'll be the Loudest Station on
the Channels, Hands Down......


Bolt the tuner to a big screen of galvanized chicken wire laid out as far
as you can from the stern up towards the bow....right against the hull.

This makes a big capacitor that couples the RF off into the sea, without
actually causing a big galvanic battery in the process. One plate is the
screen wire, the other is the ocean. The insulator between is that thin
layer of chopper gun plastic they told you was a fiberglass hull....(c;]

The bigger the screen wire plate, the better it works....no direct contact
with seawater or being grounded to anything like the engine block is
necessary....or desired, to prevent galvanic eating. Just unroll a width
of aluminum flyscreen from under the tuner screwed right thru it into the
hull, forward along the side of the hull under the stuff as big as you can.

Works great....big signal....no galvanic battery.

--
-----
Larry

If a man goes way out into the woods all alone and says something,
is it still wrong, even though no woman hears him?

"Larry" wrote in message
...
"Meindert Sprang" wrote in news:4a2f93d5$0
:

Meindert
PE1GRV



Never saw your call before, Meindert.

I only add it when the topic is highly radio-active.. :-)

Meindert

On Wed, 10 Jun 2009 06:00:40 -0500, Geoff Schultz
wrote:

I was recently corresponding with an individual regarding reefing points
and sent him a back-lit photo of the sails. While I was looking at it, I
realized how much the whip SSB antenna is tilted backwards (about 10
degrees), and was wondering what effect that tilt would have.



As a vertical antenna departs from true vertical orientation, the null
at 90 degrees (straight up) begins to fill in and the horizontal
pattern begins to show some directivity.

The effect is quite significant at a tilt angle of 15 degrees.

As others have pointed out, you probably won't notice the differences
since before and after comparisons are usually inconvenient.

OTOH, you could use the effects to advantage at the lower frequencies
for communicating over distances from 50 to several hundred miles.
Energy radiated directly overhead is reflected closer to your vessel
than energy radiated at angles from 5 to 45 degrees. To make best use
of this (Near Vertical Incidence Skywave) you might want to tilt your
whip way over (assuming mechanical feasibility) to nearly horizontal.

An internet search on NVIS will fill in the details.

Good Luck,

Chuck