I'm considering building the am/cw transmitter in the 1966 handbook
(probably in others, too). It runs a single 6146 ....
I built a similar rig, but it was weakly based on that design.
Mine had a 6GK6 oscillator and a 6146 final....

I was thinking of building a simple rig again but with a 1625 in the final.
I have about a dozen of these bottles in the junk box ....

When I find the right round tuit I want to use TEN 1625's with their
filaments series'd across the 120 VAC line in a simple CW rig. Can't
find it right now, but somewhere around here I have an article from
an old radio magazine describing just such a transmitter.

IIRC, the capacitance from ten tubes limited it to the lower HF band(s),
but it still seems like an easy way to get 750 watts!
--
--Myron A. Calhoun.
Five boxes preserve our freedoms: soap, ballot, witness, jury, and cartridge
PhD EE (retired). "Barbershop" tenor. CDL(PTXS). W0PBV. (785) 539-4448
NRA Life Member and Certified Instructor (Home Firearm Safety, Rifle, Pistol)