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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