Pat:
What are you using for your SWR measurements? If you are using an SWR analyzer,
maybe you are picking up interference from a broadcast station???
73/Mike, N7ML
Pat Barthelow wrote:
> After fixing several bugs in the transmission line, and replacing the
> BN-86 Balun on our Hygain LP 1017, the antenna is still not performing
> (or, more correctly, matching) very well. SWR generally too high (4.0 to
> 1 at some freqs) but has the characteristic (log periodic) rise and fall
> of impedance across it's design range. (6.2 to 30Mhz). In some cases
> (frequencies) the SWR is acceptable, as low as 1.2 to one. The BN 86
> balun was
> replaced with a coiled coax balun, carefully made, wound as a cylinder,
> not jumble wound.
> I am looking at the Delta (?) matching section. It
> consists of an aluminum conductor parallel to and centered on the largest
> element(s),at the back end of the boom, and which are fed at the end of
> the parallel feed of the LP. It is about
> 12 ft long, and hangs abt 8" below the big end (6.2 mHz end) LP
> element(s). It is attached to each element at it's ends, with aluminum
> strap. It was bent up slightly due to catching a nearby wire antenna,
> and I wonder if it's positioning or spacing is critical to matching the
> LP. Any ideas?
>
> 73, DX de Pat, AA6EG/N6IJ
> "The Contest Station from the Government"
>
> Marina Amateur Radio Contest Station; N6IJ
> 599 DX Drive
> Marina CA 93933
>
> aa6eg@tmx.com
>
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