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Bruce in alaska Bruce in alaska is offline
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First recorded activity by BoatBanter: Dec 2007
Posts: 153
Default Tilted SSB Antenna

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
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