The one other thing I would wonder about is the output-tank circuit.
The tube has a lot of output capacitance, and this appears in parallel with the plate-tune capacitor. Puts a severe upper limit on the capacitance that it can add to the circuit and still resonate the coil.
When the coil is trimmed for best output, that control will tend to be near, but not all the way to the minimum end of travel.
If it goes all the way to the end without showing a peak, the coil needs to get spread out a bit. What usually works best is the max coil inductance that still permits you to peak the plate-tune near but not quite at the minimum-capacitance end.
73
The tube has a lot of output capacitance, and this appears in parallel with the plate-tune capacitor. Puts a severe upper limit on the capacitance that it can add to the circuit and still resonate the coil.
When the coil is trimmed for best output, that control will tend to be near, but not all the way to the minimum end of travel.
If it goes all the way to the end without showing a peak, the coil needs to get spread out a bit. What usually works best is the max coil inductance that still permits you to peak the plate-tune near but not quite at the minimum-capacitance end.
73