Richard Fry wrote:
"At least there appears to be an acknowledgement that some RF amplifiers
do not have a source impedance that is the conjugate of their load
impedance."

Those may be anomalous. I recommend King, Mimno, and Wing to anyone
desiring the complete story on the conjugate matches.

To the extent that the amplifier is designed for a performance on demand
that stresses it to its maximum safe dissipation, an amplifier of the
Class C variety is designed for a perfectly matched load. It`s the
economical thing to do.

You supply the tube with about all the volts it can safely take. Then
you supply it with just enough load impedance to limit its current to
all it can take under the heaviest loading it well encounter. That would
be when it is conjugately matched to a 50-ohm load, the usual cable
impedance specification.

The tank circuit is mostly a harmonic filter providing a very high
impedance to the fundamental frequency and shorting out the harmonics.

Best regards, Richard Harrison, KB5WZI