Since my earlier post (dealing with the question of what is peak evelope
power output in an AM transmitter), I've been doing more scrutinizing
of tube Ip/Vp characteristic curves. They are much more non-linear than
the impression you get from just looking at the curves. Also, it is rare
or almost non-existant to find Ip vs screen voltage!

Lets look at the venerable 833 (from my RCA TT-3 transmitting tube
manual). This is a KW input class C triode.

From the curve:
at zero grid volts, 1 kV on the plate gives 175 ma plate current
2 kV 500 ma
That's more than a doubling of Ip for a doubling of Vp

at minus 50 grid volts, 2 kV on the plate gives 50 ma plate current
4 kV 750 ma

looking in my RCA receiving tube manual (RC-20) I found for a 6FG6
a sharp cutoff tetrode that only at zero grid volts was there a near
linear relationship between plate current and plate voltage (meaning zero
current at zero voltage, and a straight line [which actually deviated
slightly from a straight line] with some slope. But at 100 v on plate,
current was 14 milliamps, at 200 v on the plate, plate current was 34
miliamps. Definitely NOT a linear relationship. For the 6EM7 a triode,
and at any of a wide range of grid voltages, plate current could be
doubled with only a 15-20% increase in plate voltage.

My thinking on all of this leads me to claim that anyone who can start
with a 100 watt carrier from an AM transmitter and make a few assumptions
about 100% modulation and come up with a _calculation_ of something like
400 watts of peak power and represent that as having something to do with
reality is pure conjecture.

If anyone wants to put an appropriate oscilloscope on the transmitter output
and measure the RF voltage of unmodulated carrier into an appropriate load
and then measure the peak RF voltage when the carrier is modulated, then
and only then do they have a reasonable _basis_ for making a claim about
peak (instantaneous) output power.