Efficiency and maximum power transfer
Owen Duffy wrote:
"The Class C amplifier is a switch...
If you say it enough times, will it become true?"
True is true no matter what anyone says. I`ve never seen Terman
misspeak.
On page 255 of his 1955 opus Terman wrote:
"---the Class C amplifier is adjusted so the plate current flows in
pulses that last less than half a cycle."
On page 450 he wrote:
"The high efficiency of the Class C amplifier is a result of the fact
that plate current is not allowed to flow except when the instantaneous
voltage drop across the tube is low; i.e. Eb supplies energy to the
amplifier only when he largest portion of the energy will be absorbed by
the tuned circuit."
Sounds like a switch to me. When switched on, voltage drop across the
tube is low. When switched off, voltage drop across the tube is Eb, but
since current is zero, no power is lost at that instant in the tube.
Best regards, Richard Harrison, KB5WZI
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