On 9/19/03 12:47 PM, Gene Bigham at jbigham2@kc.rr.com wrote:
>Anyone have experience with the Cushcraft A3S and to what extent a
>director or reflector getting out of tune might have on the SWR of the
>driven element?
Actually, yes.
When I first put up my A3S, I musta been in a hurry or something. The
director outermost elements (eg 20m) were far too short. For some reason,
I measured them wrong and they were about 8 inches short, each side.
I never noticed any problem with the SWR. I had it up for 6 years, then
took it down when I moved. Later, when W7OT put it up at his station in
GA, he noticed the marks on the aluminum tube that indicated the wrong
positioning.
So, I don't think the director or reflectory mispositioning has much
affect on the SWR. It will certainly alter the pattern.
When I finally put the A3S back up at my QTH 2 years ago, I carefully
measured and selected K7LXC-style positions for the elements -- half-way
between the CW and MID settings. This is what Steve recommends for the
40-2CD, but I found it yeilds good SWR curves for the A3S as well.
At 15m high, and fed with 85 feet of RG-213 through a bead balun, my A3S
shows SWR curves straight out of the specs.
Bill Coleman, AA4LR, PP-ASEL Mail: aa4lr@arrl.net
Quote: "Not within a thousand years will man ever fly!"
-- Wilbur Wright, 1901
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