[TowerTalk] mismatch loss and SWR

[DavidC]

> Not quite. It only makes one trip Dick, and some of the concepts in the
> text above are incorrect. This is not the proper reflector for a
discussion
> of PA's, or conjugate matching. I'll make one final (I hope) comment on
> this topic. 
> 
> Wave theory is just another way of explaining circuit action. Nothing
> really bounces back and forth at all, it's just a concept. Power flows
only
> one direction, and that is from the source to the load.
> 
> No, bouncing power is a concept or "tool" we use to understand how a
system
> behaves. One reflection is all you get in this type of analysis. That is
> what "creates" the standing wave.
>  
> 73 Tom

Thanks for sharing this, it simplifies this greatly for me!

Quick clarifications:

1.  Loss issues in the system only become significant if when multiplied by
3 they are intolerable?

(Well, wait, let me clarify what I mean.  If the total energy delivery
system loss is 10% total, then it takes 1000 watts down to 900 watts on the
first pass (700 watts "stays", as it were, at the antenna, and let's say
for this example that the mismatch causes 200 watts to be reflected).   The
loss takes our 200 watts of reflected power down to 180 watts on the return
trip to the TX, and again down to 162 watts on the final trip from TX back
to the antenna (so the final total power available to the antenna to
radiate is 862 watts rather than the 1000 watts originally dispatched)? 
Thus the total cost of Loss is 138 watts in this case, but the added cost
due to the Mismatch is only 38 watts.)

2.  May there be multiple reflections due to multiple points of mismatch? 
(e.g. tuner, switch, connector, lightning arrestor, etc. not working
properly.)

Thanks for helping!  73, DavidC  AA1FA

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