To: lancair.list@olsusa.com
Date: Tue, 10 Nov 1998 08:35:43 -0800
Subject: antenna
Message-ID: <19981110.083544.-427533.1.refroelich@juno.com>
From: refroelich@juno.com (Robert E Froelich)
Mime-Version: 1.0

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One comment on home made antennas.  For the Comm antenna, borrow a
Standing Wave Ratio (SWR) meter from a ham radio operator.  With the
antenna in place on your aircraft, use a handheld comm, hook it through
the SWR to your antenna.  Then check it from 118.0 to 135.95 every 2 Mhz.

Draw a graph of the results.  Then cut or add to the ends until you get
the best flat curve.  Be sure the antenna elements are at least 1 inch
wide.  Band width is dependent upon antenna element width (or diameter if
round).

When I started, on several frequencies I was only getting 15% radiation. 
When I finished, I got at least 65% radiation on the poorest frequency.  
 

If you can get a frequency generator that covers the VOR frequencies, you
can do the same on the VOR antenna.  What it radiates is proportional to
what it will receive.

Bob, KE7OV