Hi Cecil,No...you don't want your counterpoise in the water. The reason is that
RF does not penetrate very far into salt water.The only exception would be if
the water was only a few inches deep like in a salt marsh.73,Gary K9GS
-------- Original message --------From: Cecil <chacuff@cableone.net> Date:
1/8/20 12:01 PM (GMT-06:00) To: Ignacy Misztal <no9e@arrl.net> Cc:
Topband@contesting.com Subject: Re: Topband: Problems with inv L on pier over
salt water I’m far from an expert but if you were over salt water I would have
placed the counterpoise in the water.I’d be curious what others think.Great
experience though...CecilK5DL> On Jan 8, 2020, at 11:07 AM, Ignacy Misztal
<no9e@arrl.net> wrote:> > I would like to share my experiences with 160m
operations during the SP> contest last December.> > My rental house in St
George Isl FL had a 140 ft pier over the bay. Also a> power line to the end of
the pier raising questions about RFI.> > I set inv L at the end of the pier
with 40ft Spiderpole, 70ft horizontal> and 70ft radial on the pier. Horizontal
with 24 gauge enameled wire for> low weight, and the rest with 18 ga THHN.
Matching was with a transformer> on FT140-61 and coil on T200-2. Minimal SWR at
1.84.> > One hr before the sunset the EU was booming. RFI was pretty high but
the> signals even stronger. I tried to use KX3 and Expert 1.3k combination,
but> SWR become very unstable causing the Expert to turn off. I was looking
for> culprits but could not find anything. Frustrated, I was forced to use>
FT-891 at 100W.> > The setup was still pretty good as several EU answered my
CQ.> > The next day I noticed that the radial on the pier that was touching>
underneath (salt water sprayed) had melted insulation. Apparently this> caused
sparcing and then variations in SWR.> > I relocated the radial away from the
pier, over the bay. The resonance> moved from 1.84 to 1.96, and the impedance
at resonance reduced from 40 to> 25 ohms. So the pier (or power line) was
loading the antenna, surely> generating losses. Operating with a KW was no
longer a problem.> > Here are my lessons:> 1. 40ft Spiderpole is enough for
highly efficient inv L over salt water.> 2. Beware of insulated wire touching
anything and especially wet and salty> at high power.> 3. Even with problems,
the performance of an antenna over salt water is> terrific.> 4. Matching units
do not have to be big.> 5. With good antenna, $550 FT-891 is OK.> > Ignacy,
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