At 07:27 PM 12/18/99 EST, you wrote:
>
>
>Here's one for the computer model nuts (freaks....kooks....loonies???) to
>play with:
>
>
>
>Triple stack of C3E at 90/63/36 feet versus two stack of C31XR at 92/55.
>
>Both of those arrays are within reach of your "average guy" with room for a
>single tower. Heights are based on separation of 27 feet for the C3s and 37
>feet for the C31XRs and take into account likely guy wire placements on a
>Rohn 25/45 type tower. Using F12s numbers the C3E stack will be about 17
>square feet of load and the C31XR stack about 22 sq feet.
>
>I can think of pluses and minuses to each array. Curious what others might
>come up with.
While I'm not sure that a 90-foot tower is really attainable in many
"average" circumstances, the 3-stack of short-boom 2-elelement antennas is
very attractive to me. In particular, the relatively low F/B ratio and
broad pattern can be helpful in contest situations. Using just one C-3, I
find I can usually work mults off the back or on the edges of the front
lobe without turning the antenna, and the fairly strong backward signal
helps to hold a run frequency, at least for us on the East Coast.
I was glad to see Kurt's caution about the area figures -- I would ideally
like to have such a stack with a small 2-element 40-meter beam on top, but
this would be too much for the published ratings of the Rohn 25 tower I
have, even in this relatively benign wind environment.
73, Pete Smith N4ZR
n4zr@contesting.com
Sometimes a tower is just a tower
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