Greetings Rune,
Your selection of 30 ohms for the 90 degree cable is likely the cause.
If you calculate 90 degrees of cable looking into 16.5 ohms you actually
get 54.55 ohms transformation.
If you had a cable combination that was 28.7 ohms instead of 30 you would
get your near perfect match.
Or if your antenna was actually 18 ohms and a 30 ohm cable you would have a
match.
I don?t think just changing your matching cable length will help that much.
Someone else may have more information on that.
Perhaps a little extra length on your element with a bit of parallel
capacitance at the driving point to get the resistance up to 18 ohms would
work.
Parallel capacitance could be made up with extra length on the matching
cable.
Lee K7TJR OR
-----Original Message-----
From: Topband [mailto:topband-bounces@contesting.com] On Behalf Of Rune via
Dropbox via Topband
Sent: Monday, March 23, 2015 4:47 AM
To: topband@contesting.com
Subject: Topband: Rune Øye shared "1_4wave_transformer.docx" with you
Rune's message:
"Hi all,
Regarding 1/4 transformer I sent earlier today
I sent an mail earlier today but didn't know that I couldn't add attachment,
however here is a link to drop box to share the document.
73 Rune LA7THA"
Click here to view:
https://www.dropbox.com/l/0QSKn8NZifyHPLW1iSjnzg?text=1
(Rune shared this file using Dropbox. Enjoy!) _________________ Topband
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