[Towertalk] Dumb Question (swagged elements)

[Don Havlicek]

Dino,
I've used those same element segments to build MANY antennas over the years.
the simple answer is NO .. it won't affect the electrical length as the 
'capacitor' isn't long enough to be a significant portion of a 
wavelength on the band of interest, and it won't have sufficient 
'capacity' to make a difference.
Good luck
Don
N8DE


You wrote:
I have a couple of old Hy-Gain antennas with swagged elements.  I get 
these for free when I take down old towers.

Lets say, for argument, that we have two elements.  One slides inside 
the other, which is swagged in order to meet the outside diameter of the 
first one.

These two elements can be tuned to different frequencies by adjusting 
the length the first element slides INSIDE the other.  To exaggerate, 
lets say the first element is 12" inside the swagged element, but the 
only contact area between the two elements is the few inches where the 
second element is swagged.  The rest of the first element is hanging out 
"in free space" (for lack of a better term).

Here is the question...will the element INSIDE the other affect the 
electrical length of the entire assemble due to the extra metal in "free 
space"?  Although it is a direct short, will there be any capacitance 
much like a gamma match where one material is suspended inside the other?

Dino...k6rix@arrl.net