I'm sure Tom will answer, but I can't resist taking a stab at it: if the
total system loss is 10%, 900 watts will be radiated by the antenna. The
power really only flows in one direction, right? Of course, your SWR meter
will report a better match than really exists, because the measured
reflected power will show the 10% system loss. So, instead of computing SWR
based on 1000f/200r, the meter computes it based on 1000f/180r. I certainly
see that effect when I compare SWR at the load and transmitter ends of the
360 feet of coax going to my antennas!
73, Dick, WC1M
>(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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