"Bottom line -- SWR is DUMB, STUPID, and USELESS as a measure of
antenna performance." --> TRUE
"I can LOAD a lightbulb, but it's a lousy antenna. --> NOT SO TRUE
I once used a 60w light bulb as a dummy load. But on 10m it worked JA
59. --> TRUE
73 de Phil - N8PS
Quoting Jim Brown <k9yc@audiosystemsgroup.com>:
My Ten-Tec 238 tune my 80 double ext.zepp on all bands 160-10 with
a 4-1 balun 182 ft of 400 ladder line then the 4-1 with 20ft of coax.
No, it doesn't "tune" your 80 double ext.zepp, it creates a match
between the transmitter and the FEEDLINE that allows the transmitter
to dump power into the FEEDLINE. How much of that power gets to the
antenna depends on the mismatch between the feedline and the
antenna. It's pretty common to lose 10 dB between the transmitter
and an "all band" dipole. 10 dB is 90% of the transmitter power.
I can make my 80M dipole look like 1:1 on 30M to my 200W amplifier,
but mismatch loss is determined by the match between the ANTENNA and
the FEEDLINE, and I would be burning 180 of those 200W in the
feedline.
Bottom line -- SWR is DUMB, STUPID, and USELESS as a measure of
antenna performance. I can LOAD a lightbulb, but it's a lousy antenna.
73, Jim K9YC
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