[Public-list] VHF antennas

[Brian Palmer]

Roger,

You are better off with the standard 3db sailboat antenna on the top of
your mast.  As I understand, some of those long fiberglass powerboat
antennas offer up to 25db gain, however, they achieve this by focusing
the transmit and receive signal into a narrower beam top to bottom.
Since sailboats heel, a higher power focused antenna would focus the
beam into the sky and water the more the boat heels or in a rolling sea.
If you could somehow mount the high gain antenna on a gimbal, then it
might work, but if the gimbal rocked while you transmit or receive, the
signal sill fade in and out.

Your best bet it to install a standard 3db antenna as high as possible,
and be very careful when you run the cable not to kink or bend it in too
tight a radius.  Also, soldering the connections and sealing them from
the weather will help keep your antenna connection strong in future
years.

Here's a quick illustration to show what I mean:
http://www.digitalarsenal.com/antenna_theory.jpg

-Brian Palmer
#288 L'Esprit


-----Original Message-----
From: public-list-bounces at alberg30.org
[mailto:public-list-bounces at alberg30.org] On Behalf Of Roger L.
Kingsland
Sent: Monday, September 27, 2004 2:57 PM
To: Alberg30
Subject: [Public-list] VHF antennas

I seem to recall reading the longer, power boat type VHF antennas are
more efficient but the short ones work better at the masthead.  Because
I could mount a long antenna on my radar mast (about 12' above water), I
have the option of doing either.  Any opinions on which is best would be
appreciated?

Roger

PS - thanks for a great time during the Canadian weekend; it was great
to see everyone.


Roger L. Kingsland, AIA
Managing Partner
Kingsland Scott Bauer Associates (KSBA) 
N40° 27' 49"  W79° 57' 59"
3441 Butler Street
Pittsburgh, PA 15201
www.ksba.com

1(412) 252-1500 X101 - Office & Voice Mail
1(412) 779-5101 - Mobile (no voice mail)
1(412) 252-1510 - Fax

_______________________________________________
Public-list mailing list
Public-list at alberg30.org
http://alberg30.org/mailman/listinfo/public-list



 1096315034.0