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[TowerTalk] Re: Question on linear loaded antenna

To: <towertalk@contesting.com>
Subject: [TowerTalk] Re: Question on linear loaded antenna
From: n4si@pobox.com (n4si@pobox.com)
Date: Mon, 19 May 1997 23:45:40 +0000
> Just read an article and came across a term I don't know.  What is
> linear loading in a beam antenna.  

There may be some real bright people who can give a better answer, 
but in the meantime, here is a start:

The term "loading" as used here means substituting some electrical 
value for space. In other words, if you were to build a 40M dipole, 
you would need about 66'. If your space available was less than that, 
you could do a number of things: coil, bend the wire, get on 20M, 
etc. All except the last are forms of loading.

In linear loading, some of the element is folded back on itself to 
shorten the element.

The KLM 40M element, for example, looks something like this:

        --)----------------------|
---------)----------------------|-#####-|------------------------------
        -)---------------------------------|

Where #### is an insulator, ------ is tubing, | is a connection 
between two tubing elements, and ) is a jumper between the two short 
bars over the long one.

Clearly I am not an ASCII artist, but this may help.

In the KLM, a 33 foot half element actually only takes up 20 feet 
because of the linear loading.

73, Rod N4SI
    The DXer formerly known as N9AKE
         (c) 5 November, 1996

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