[TowerTalk] Re: Antenna Question

[N6CW]

In a message dated 98-05-13 01:43:34 EDT, you write:

<< 
 Hello all....
 
 I will be installing a new tower soon and I would like to install a 40 meter
rotatable
 dipole above my yagi...  my problem is that I can't place the dipole more
than a few feet
 above the yagi.   Is it posible to do this without degrading the performance
of the yagi ?
 Since the 40 meter dipole element is much longer than the yagi elements, I
was hoping 
 that this would reduce the coupling effect. Just a guess...
  >>

This message was posted on the DX reflector by someone else but it got me
thinking. I am currently planning my antenna set up and trying to figure out
how to put up all the antennas I need without totally overloading my 70 foot
tube. An article by N4KG in a recent issue of the NCJ reminds us of the old
trick of matching the boom of a large HF yagi/tribander for use on 40/30
meters. This seems to be a great idea and a "freebie", another antenna without
adding any more square footage. So the question is: why buy add on kits to add
40/30 to a tribander when this is so easy to do? Is there a performance issue
here? It would seem that this would be a more efficient antenna than adding a
trap extension or hanging a seperate trapped dipole above or below the
tribander. The only question I could see is a possible bandwidth problem due
to a short boom, but even adding short extensions to the ends of a boom would
an easier solution than adding a larger amount aluminum as a seperate element.

Any ideas on this?

Terry/N6CW

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