No mystery about the W5GI antenna anymore.
Gene Hinkle, K5PA analyzed it at his antenna symposium at Austin Summerfest
Texas State Ham Convention in August.
The only mystery was that the original modelers W5GI relied on did not
understand you cannot directly model the stub element section. If you drop
the in line stub vertically off the antenna, it is electrically equivalent
and you can model the rest of the antenna using conventional NEC type
modeling. Then factor in the well known characteristic of the quarter wave
stubs as to phase and you are done. It is a nice gain antenna alternative
to the G5RV. Clever idea by W5GI.
It is a collinear antenna, using phasing stubs integral to the elements on
each side of the doublet.
Thus, it presents some gain on 20m, much like the G5RV does.
The entire Antenna presentation of the K5PA seminar is available on the web.
Google for
"Gene Hinkle K5PA".
-Stuart
K5KVH
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