[TowerTalk] C4XL Driven Element Placement

[K7LXC]

In a message dated 97-12-24 14:45:17 EST, you write:

> Ok I have measures the swr with a msj anz here when tower is cranked down at
> 21ft
>  here.The swr is readind right at the 7.03mz like it should.When the tower
is
>  raised it drops until the tower is at full hieght at 55 ft.The measurement 
> there
>  is 4.26mz.

    Okay, I'm going to assume that msj anz means an MFJ antenna analyzer. Did
you measure it at the feedpoint or what? Do you measure it at the same place
both nested and extended? I'm just trying to figure out what you're doing and
why raising it up changes the SWR that dramatically. What is different about
each measurement? What else is on the mast? Do you have a balun inline? Which
type? What's the SWR without the balun?

>Tom it is not the element that I have a problem with here but the
>  element to boom backet is in the wrong place.Yuo see when the mast is in 
> place it
>  sits inside the hairpin turning network of the 40 mete driven element.If
you 
> still
>  dont understand I will be happy to send you a picture of it.

     I think the element is close to the boom-to-mast clamp and mast. Feel
free to shift/slide the boom so that it pushes the element farther away from
the mast. You don't need much clearance. How much do you have? 

     I don't recall a hairpin match on a Force 12 linear loaded antenna. What
they use is a coil across the feedpoint that you pull or squish to adjust the
SWR once the driven element is tuned. If the hairpin is for the 20M (I don't
recall one for that antenna offhand), do you have mistakenly mounted on the
40? If it does indeed use a hairpin, flip it over 180 degrees and have it
pointed AWAY from the mast. 

    Are we getting anywhere yet?

73,  Steve   K7LXC

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