Amplifier Theory vs Transmission Line-Antenna System Theory
I understand that the ARRL has dropped Walt Maxwell's,
W2DU, materials from the new edition of the
Antenna Book, and stopped printing
"Reflections", Maxwell's book about antenna tuners,
feed lines,stubs, baluns and antenna systems.
W. Bruene, W5OLY (pronounced "Breenee?) (of Collins Radio
fame, who "wrote the book about SSB amplifiers, or at least
a chapter or so thereon) has not agreed with Maxwell's assertion
about conjugate matching in the antenna system. He includes
the power amplifier and claims "it" wants to see a rather high
VSWR when loaded correctly. He published the results of tests
he had run in QST, 1993, sometime, I think I recall.
Anyway, whatever it was he measured did show high VSWR,
but was not clear to me what was being measured. Per Bruene,
the in-the-shack antenna tuner is just an impedance matcher,
which together with the amplifier output circuit, gives
the power output tube(s), or that circuit set up,
the high vswr desired, and the feed system the impedance
it wants to see.
It took a few years, but somehow these results and his tenacity
at pursuing Maxwell's work has resulted in the ARRL dropping
Maxwell's material which they have used for years! Maxwell's
book "Reflections" was based upon a long running series in QST,
1973 into 1976. Now the ARRL has dropped the book, I
am told. Seems a shame, I read through the book in nearly
my first sitting with it; very well written and seeming to
be presenting the truth about current and waves in our HF
systems, and the best ways to get our rig's power
out the antenna.
Seems Maxwell is the antenna system man -- eg, all his work on
space craft feed/antenna systems, and Bruene is the circuits man.
Anyone on here really know what is the truth in this matter??
I have written correspondence with both men, and they just
disagree with one another on just about everything. Each believes
he has data and theory showing the other's ideas are not
correct and are not true.
73, Jim, KH7M
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