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Re: Topband: an antenna problem

To: <topband@contesting.com>
Subject: Re: Topband: an antenna problem
From: "Mike Smith VE9AA" <ve9aa@nbnet.nb.ca>
Date: Mon, 11 Jan 2016 09:42:46 -0400
List-post: <topband@contesting.com">mailto:topband@contesting.com>
Hi Mike, 

 

Not sure why you chose a 1/2wave,. but that aside.

I am not where your trees are located etc. but if you can get it close to
125' then you have a near perfect 1/4w.

 

Second option and what I normally do is go around 160-165' for a 3/8ths wave
(5/16th if you prefer)_ and feed it with a large air variable series cap,
say around 800pF or thereabouts.

Put that cap under a 2L pop bottle. (would that be a 4qt soda bottle? hi)
for wx protection (I learned that trick for protection of stuff from
VE1ZZ...tweak the cap for a perfect match.

 

Mike VE9AA

 

i normally run a half wave inverted L, 125 up and 125 out. with our great

winds here in the pac north west this December, my inverted L got caught

in a tree about 50 feet from  the supporting tree i cannot pull the wire

down from either end.

 

two options: 1)take the far end and add a bit (60 feet) and make it a

very fat quarter wave or 2) hopefully pull the loose end (far end) and

break it up at the tangle in the interfering tree that is about 50 feet

away from the supporting tree

 

now i would have a pretty long inverted L with a short horiz end, maybe

then it would be a 3/8 wave antenna.

 

pulling it all down would be difficult..............

 

the original inserted L was fed against an FCP

 

 

thanks

 

mike w7dra

 

Mike, Coreen & Corey

Keswick Ridge, NB

 

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