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Topband: phasing line lengths for phased verticals

To: "topband@contesting.com" <topband@contesting.com>
Subject: Topband: phasing line lengths for phased verticals
From: DALE LONG <dale.long@prodigy.net>
Reply-to: DALE LONG <dale.long@prodigy.net>
Date: Sat, 17 Nov 2012 15:56:26 -0800 (PST)
List-post: <topband@contesting.com">mailto:topband@contesting.com>
Until recently, I had phased verticals on both 80m and 160m and lots of 
beverages. (this was in a woods, and not my property)  Then the loggers came 
and destroyed all.

In addition to the antennas, the phasing lines were torn up, and broken and 
needed replacement.  For 160m I use the Christman method with .71 and .84 
wavelength lines. For 80m I use a Comtek PVS-2 controller.


In replacing the 80m phasing lines today I made a stupid mistake, I dont know 
what I was thinking, but I carefully measured and soldered two identical 1/4 
wave lengths of new coax.  I tested them on my AIM 4170 and they were nearly 
identical, exactly on the design frequency.  Then I went to install them and 
guess what...of course they were too short.  I have worked with phased 
verticals before and I know that you often need to use 3/4 wave phasing lines, 
but I was too intent on measuring and soldering and making the repairs.

So now I have two questions.

1. for 80m phased verticals that are 1/2 wave apart (66 feet), what will be the 
pattern?  It's not the same as 1/4 wave spacing, so what really is happening?

2. what is the best length of phasing line to use.  Should I use 3/4 wave 
phasing lines?  Should I avoid using 1/2 wave phasing lines?

Thanks

Dale - N3BNA
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