At 12:16 AM 3/10/97 +0000, you wrote:
>The ARRL Antenna Books for many editions now have all
>carried Walt Maxwell's, W2DU, work and words about conjugate matching
>and antenna tuners (transmatches). I am not aware that the ARRL
>now is doubting Walt's work. If so, it is because of measurments
>by Walter Bruene, W5OLY. See his article, "RF Power Amplifiers and the
>Conjugate Match", QST, Nov. 1991, pg. 31 and following. Also see
>Bruene's article, Technical Correspondence, QST, May 1992, pg. 95
They have purged Maxwell's correct work based on Bruene's incorrect
measurements.
Bruene's measurements used a direction coupler that gave him no idea
what the source impedance was. He just "guessed" the impedance based on
a directional coupler saying there was imperfect termination. A
directional coupler is NOT an impedance bridge.
Maxwell was correct, but now his work has been tossed out and the ARRL
quit publishing his book based on one flawed measurement on three pieces
of gear.
<snip>
>for several years! Maxwell's book, "Reflections", stands on
>it's own merit. There are few technical books that I find
>difficult to put down, but his, I nearly read cover to cover
>when I first discovered it. Talk about overturning Old Ham
>Tales!!
Walt is an antenna and transmission line guy. He knows wave theory very
well.
> Walter Bruene, on the other hand, wrote all of
>Chapter 14, "High-Power Linear Amplifiers", over 30 pages long,
>in the excellent text, "Single Sideband Principles and
>Circuits", edited by Sabin and Schoenike, published by
>McGraw Hill, 1987. 22 authors within this excellent
>book, all by Collins Radio and Rockwell men. Many of these
>men, along with Art Collins of course, are the Fathers of our
>amateur SSB technology.
Those guys are circuit analysis guys, and they know circuitry very well.
Since this is a wave theory disagreement, in my opinion one guy who
spent his life working every day with that method (Maxwell) is worth a
hundred brilliant guys who haven't. If I wanted brain surgery, I'd trust
the opinion of one brain surgeon over 1000 podiatrists.
Especially since I measured over 15 PA's using two different methods
and confirmed Maxwell's claims.
Seeing is believing. Maxwell was correct. He was just out-gunned.
73 Tom
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