From:
Fred Hopengarten, K1VR
Six Willarch Road * Lincoln, MA 01773-5105 * 617/259-0088
e-mail: k1vr@juno.com or k1vr@k1vr.jjm.com
Big antennas, high in the sky, are better than small ones, low.
On Mon, 10 Feb 1997 14:31:13 -0500 Bill Cotter <bcotter@service1.uky.edu>
writes:
>I have installed a 40m 4-sqr array with 64-radials per radiator. About
>half
>of the radials are #14 enameled wire and the other half are #16
>plastic
>covered wire. None are bonded together as they cross. The only bonding
>between the radiator ground systems are the outer braid of the
>feedlines to
>the ComTek box. Will I expect less than perfect gain, directivity, F/B
>Ratio, or Radiation Resistance? Should I expect something more
>insidious
>like arcing, static or who knows what. Or, as I suspect, no
>discernable
>consequence..... Comments/experiences please.
Bill:
I also have a 4 square on 40, with 40 radials, each 40 feet long,
under each vertical. Where they crossed the midlines, I bonded them to a
bus wire, just as the book instructed. The system works well, BUT you
should be cautioned that at 7 MHz, my experience is that the system
doesn't work well into Europe at all, as the angle of radiation is just
too low for the New England to EU path. For JA and VK longpath in the
afternoon (local time), it is just fine. Those are very low angle paths.
But for EU, the Cushcraft 40-2CD at 90 feet is usually 18-20 dB better,
according to many tests over the past 10 years. Both antennas are fed
with about an equal length of half-inch hardline. The Yagi is better
because, at that height, it has a higher angle of radiation.
In addition, I have a sneaking suspicion that a vertical on 40 is
not as efficient as a Yagi on 40.
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