Towertalk
[Top] [All Lists]

Re: [TowerTalk] horizontally polarized antennas and salt water

To: "Jim Lux" <jimlux@earthlink.net>,"Stephen Reichlyn" <Stephen.Reichlyn@ryansci.com>,<towertalk@contesting.com>
Subject: Re: [TowerTalk] horizontally polarized antennas and salt water
From: Pete Smith <n4zr@contesting.com>
Date: Tue, 18 Jan 2005 14:00:45 -0500
List-post: <mailto:towertalk@contesting.com>
At 11:21 AM 1/18/2005, Jim Lux wrote:

Pete Smith wrote:
>
> It does, but not a bunch.
>
> I quickly modeled a 40m yagi at 104 feet over average ground versus salt
> water.  Forward gain went from 11.86 dBi (avg) at 18 degrees to 12.45 dBi
> (salt).  Takeoff angle, interestingly, went up one degree for the better
> ground plane.  Moving the antenna down 6 feet over salt water moved the
> takeoff angle up 1 more degree, from 19 to 20 degrees.
>

Just as an idle question..  I wonder if the gain change is due to a pattern
shape change (narrower main lobe), or due to a reduction in losses. The
average gain number would tell you, since it's integrated over all look
angles.

It appears to be reduced losses. The average gain over salt water is -0.06 dB; over average ground it is -0.96 dB, per NEC-2.


73, Pete N4ZR

_______________________________________________

See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions and ask for Sherman, W2FLA.

_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk

<Prev in Thread] Current Thread [Next in Thread>