The advantage of class C isn't necessary greater efficiency. By reducing the
conduction angle the tube is drawing current for a short period of time and
therefor can run cooler. It also means that the tube can be run at a bit
higher power level than it could in class B since the AVERAGE power dissipated
is the same.

I cannot quite follow your reasoning. The tube temperature is bound to the
dissipated power. And the dissipated power simply is the difference between the
average DC power and the RF output power (neglecting losses in the Pi network).
So, if varying the signal duty cycles and tube conduction angle, I anyway read
the same output power and the same DC power, the stage efficiency is the same.

HOWEVER the duty cycle of both the time transmitting vs not transmitting and
that of the signal also play a role. In other words a class C CW transmitter
in theory could be run at higher power than a class C FM phone transmitter
(even though both are usually run at the same typical parameters) since the
tube can cool between elements on CW, while FM is key down forever. Also class
B audio has a different duty cycle than a class B RF linear amplifier running
FM (don't need to be linear for FM 'thou).

In the 30's there was an article in QST on how someone ran a 200 watt tube at
a KW CW. It worked because of CW's short duty cycle, but the editor suspected
'short dashes'.

That's OK.

73

Tony I0JX