> From: herbs@vitelcom.net
> To: topband@contesting.com
> Subject: Re: Topband: water saturated ground effec
t
Paul,
>
> What you experienced could be a misleading indication as ground
> conductivity with moisture depends a lot on the actual type of soil.
> with a vertical that is less than a quarter wave the direct feed
> impedance should be very low. YES, THAT IS WHY I NEEDED THE UNUN IN THE FIRST
> PLACE WHEN I BUILT THE ANTNNA LAST YEAR-
On a dry salt lake or high salinity soil the results
> with mixing water would be more noticeable but I don't think this is
> what you have there. AGREE-
My point here is that one of the reasons the FCC requires AM stations to
> have a ground system as part of their application is so there is a
> constant radiation with a certain power level that will maintain the
> radiation pattern and microvolts per meter at a given distance. A good
> adequate radial system is supposed to prevent the very phenomenon you
> described.
HERB, I UNDERSTAND WHAT YOU WROTE, BUT NOT SURE HOW IT APPLIES TO MY SITUATION
WHEN THE SWR LAST WENT FROM 1:1 TO 5:1 WHEN I ADDED THE 26 RADIALS EXPOSING THE
MISMATCH IMPEDANCE THAT THE AMIDON UnUn WAS ABLE TO MATCH THE COAX TO THE
ANTENNA- AT THE TIME, USING THE COMBINATION OF THE UnUn, THE ANTENNA IMPEDANCE
WAS ESTIMATED TO BE AROUND 20 OHMS- I TESTED EVERYTHING AGAIN THIS
MORNING....STILL GETTING A 2.3:1 SWR MATCH WITHOUT THE UnUn, WHEREAS LAST
SEASON, I COULD NOT GET THE SWR BELOW 5:1 WHEN I DIRECTLY CONNECTED THE ANTENNA
WITHOUT THE UnUn IN LINE.........WITH THE UnUn THIS MORNING, I CAN GET IT FLAT-
ARE YOU SAYING THAT A SOAKED SOIL IN MY SITUATION IS WORSE THAN DRY DIRT?
73!
PAUL TI5/N0AH IN ABOUT 27 HOURS!!!!
>
> Herb Schoenbohm, KV4FZ
> >
> >
> > _______________________________________________
> >
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
_______________________________________________
UR RST IS ... ... ..9 QSB QSB - hw? BK
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