Hi, Chuck
Well return loss is a transmission line term that is a measure of the
reflection on the line. So a transmission line that is terminated in its
characteristic impedance would have 0 reflection, or infinite return loss or
1.0:1 VSWR. Conversely if the line was lossless and terminated in an open or
a short, 100% of the incident power would be reflected, resulting in 0dB
return loss, or infinite VSWR.
So you want to target the lowest VSWR - as close to 1.0:1 as possible. BTW,
it can be shown in the general case, that minimum VSWR will occur at
RESONANCE.
Have fun with EZNEC, it's a wonderful, powerful, and easy to use program
that have used over the years to model,design and build some wonderful
"killer" antennas that have performed wonderfully!
Have fun and keep learning!
73,
Charlie, K4OTV
-----Original Message-----
From: Topband [mailto:topband-bounces@contesting.com] On Behalf Of Charles
Yahrling
Sent: Friday, December 05, 2014 3:29 PM
To: topband@contesting.com
Subject: Topband: EZNEC 5.0 +
Just getting started modelling and looking for answers to questions not
found in manual so far. For example, what exactly is included in the Return
Loss figure shown in the SWR window? Just ground reflection loss, total
system loss, something else? Trying to understand why Return Loss is
greater for lower SWR curve values. e.g see this when toggling between std
and alt impedance. What is this suggesting, go with lower return loss or
lower swr curve?
An incomplete grasp of the fundamentals is admittedly likely here <g>.
73, chuck
--
de AB1VL
NAQCC #6799
ab1vl.com
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