Ken Smith wrote:
"Motorola AN-721 takes on the theory. AN-758 gives a practical example
matching 12.5 Ohms into 50 Ohms."

As King, Mimno, and Wing said, a conjugate match is required to get
maximum power out of the radio.

Terman says the same on page 76 of his 1955 edition of "Electronic and
Radio Engineering."

There is also an Eimac application note on matching their tubes to a
load on the final amplifier.

If Larry, Moe, and Curly published an application note, we`d have a
crowd of skeptics here. See Terman`s Fig. 3-21 on page 77 of his 1955
edition.

Best regards, Richard Harrison, KB5WZI