> It isn't that difficult to measure a PA and prove this, yet most
> people spend far more time arguing than measuring.
Observations of a common layman.....
Bruene and Maxwell both agree that there is no conjugate match
from the plate block back toward the tube and plate choke. Bruene
maintains that there is no conjugate match anywhere. Maxwell maintains
that there is a conjugate match only from the loading cap. to the antenna.
Maxwell maintains that only part of the power is dissipative. The dissipative
power and non-dissipative power join together at the input to the plate block
cap. No linearity or sine wave is achieved until the pulsed power from the
two sources (tube and power supply which do not occur in sync) are smoothed
out by the flywheel action of the tank circuit. Only the dissipative power gets
lost
as heat which is only 20% or so in a class C amplifier and 40% or so in a class
B amp. Thus, class C amps can have 80% efficiency and class B amps 60% or
so, and still have conjugate match from the loading cap to the antenna.
I hope I am in the ball park here, and have whetted a few appetites for more
knowledge out there. Should Bruene choose to reply to Maxwell's latest
article, I think we will find the main disagreement was how far back from the
load the conjugate match occurs.
(((73)))
Phil, K5PC
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