Hi Chuck
This whole thing has gone beyond useful.
> Once again im confused. (or dont understand). If its not gain what is it?
It is as much "reflection gain" as the mistermination is "reflection loss".
Reflection loss does not REALLY mean you have that amount of loss except
under VERY special conditions, and those conditions are rarely met in the
real world.
Reflection gain, from a matching network, is only a way of saying the
mismatch effects called "reflection loss" have been canceled. It is
engineering jargon, that is all.
Mismatch loss, match efficiency, standing waves expressed in dB, reflection
coefficient, percentage forward power, and so on are just ways of
expressing the thing we call SWR. If you know SWR, you can get the others
or vice versa.
Contrary to common misconception and folklore, the ONLY effect of SWR in
systems we use
is an increase in system loss. The amount of loss increase is a function of
matched line loss and SWR.
Even a very high SWR has no measurable effect on performance if the line is
a low loss line like open wire line.
Systems experience the same effects on receive as on transmit, and the
effects are covered very well in laymen's terms in the book "Reflections"
as well as many more complex engineering texts.
There is no reason for a ham to use terms like reflection gain, match
efficiency, mismatch loss, and so on in day to day technical
conversations, since they are all expressions of SWR. That's why I fought
hard to have "Match Efficiency" and other useless and confusing crap
removed from the MFJ analyzer. I was supported by Roy Lewallen and several
other well known engineers in this task.
If those terms confuse professionals, they will certainly confuse amateurs.
Jargon can be very misleading.
73 Tom
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