Tom Donaly wrote:
Cecil Moore wrote:
You mean like Ptotal = P1 + P2 + 2*SQRT(P1*P2)cos(a) ? :-)
The first time I saw that equation was in Dr. Best's QEX article.

Yes, and you didn't believe it when you saw it.

Your memory is slightly faulty. What I objected to was Dr. Best's
assertion that 75w + 8.33w = 133.33w. It still doesn't, never did,
never will, and violates the conservation of energy principle.
What Dr. Best apparently failed to realize is that the extra 50
watts of energy required to balance that energy equation does
NOT come from waves P1 and P2 but instead comes from wave
cancellation of waves P3 and P4 on the source side of the match
point. Wave P1 contains 75 watts and Wave P2 contains 8.33 watts.
Without a source of constructive interference energy, they cannot
add up to 133.33 watts. That source is destructive interference
energy, -2*SQRT(P3*P4), from the source side of the match point
which supplies the +2*SQRT(P1*P2) constructive interference energy
to the load side of the match point where (P1*P2)=(P3*P4). At an
impedance discontinuity in a transmission line, far away from any
source, all constructive interference energy must necessarily be
balanced by an equal magnitude of destructive interference energy
in order to satisfy the conservation of energy principle.

This is all explained in my "WorldRadio", Oct./Dec. 2005 articles.
Unfortunately, most of the Greek letter Thetas didn't make it
through the conversion process and wound up as underline marks.
Part I is already on my web page under "The Rest of the Story"
along with a couple of remarks about forward power, reflected power,
superposition, and interference. Part II will appear on my web page
after Christmas.
--
73, Cecil http://www.qsl.net/w5dxp