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Topband: Shortend Vertical model questions

To: <topband@contesting.com>
Subject: Topband: Shortend Vertical model questions
From: k9ay@k9ay.com (K9AY)
Date: Mon, 11 Feb 2002 16:42:53 +0000
Tony

Tom W8JI's comments are good, and my 2 cents is that your modeling
is "in the ballpark" concerning bandwidth, feedpoint Z and increased 
loading inductance as it is placed higher on the structure.

I have built several short verticals for DXpeditions (including the recent
VP8GEO and upcoming TI9M). With each update of the design, I have
abandonded base loading coils as too lossy, then minimized all loading 
coils in favor of inverted-L or T type top loading.  I'll second Tom's 
suggestion to increase the top loading with a larger hat or wires--you 
will be a LOT happier with the results!

73 and good luck!

Gary, K9AY


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