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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