Years ago I used to operate mobile frequently, on 20 & 40 Mtrs. Many times
I noticed when crossing over larger rivers, that received signal levels
would improve considerably. I never knew if it was the water or the metal
used in construction of the bridge that caused the improvement. When I
reached the other side of the river, received signals would drop back down.
Can't recall anyone ever commenting that my transmitted signal level
increased while crossing the river though.
73,
Tim - N3XX
----- Original Message -----
From: <HansLG@aol.com>
To: <towertalk@contesting.com>
Sent: Tuesday, March 17, 2009 10:45 PM
Subject: [TowerTalk] Fwd: Vertical in pond
> Hi Guys,
>
> Water has a dielectric constant of around 80, high enough to reflect most
> anything, RF included. Beside getting a good ground (read low resistance)
> you
> also need a low loss surrounding to get a nice reflex of the RF leaving
> the
> vertical. (Horizontal radiation is not so sensitive to this, I am told.)
>
> You should get good coverage in the direction of you pond. With the
> vertical
> in the middle of the pond should be good in all directions.
>
> I always wondered about this and know several has with their QTH next to
> water, salt as well as fresh water ponds/lakes. They all sound better than
> "the
> rest of us".
>
> Would suggest you put a vertical i a boat/float of some sort. You could
> then
> float a feeder on the water out to the float/boat. Would probably be a
> neat
> article in QST.
>
> 73 de N2JFS
>
> Hans
>
>
>
> ____________________________________
> From: n4zr@contesting.com
> To: ve3zi@rac.ca, towertalk@contesting.com
> Sent: 3/17/2009 8:25:28 A.M. Eastern Standard Time
> Subj: Re: [TowerTalk] Vertical in pond
>
>
> Isn't it more likely that the ground characteristics in that location are
> more favorable than in the previous one? I can imagine ground well
> saturated with fresh water as having a sufficient quantity of ions in
> solution to improve its conductivity considerably. The fresh water
> itself,
> on the other hand, probably doesn't matter. Or does it? Anyone have
> anything beyond anecdotal experience to pass on?
>
> 73, Pete N4ZR
>
> At 09:20 AM 3/17/2009, Roger Parsons wrote:
>
>>Jim
>>
>>I'm not sure that this is exactly analagous, but I have a tri-band
>>vertical mounted right at the edge of a reasonably large lake (~0.5km x
>>20km). I found that that dramatically improved its performance compared
>>to
>>mounting it 100m away. The improvement was at least 10dB which changed it
>>from being a waste of time to a useful second antenna - and the radial
>>system (lots) was identical in each case.
>>
>>73 Roger
>>VE3ZI
>>
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