[Boatanchors] Link coupled output?

[Ron]

The whole idea of using a output tuning network is to transfer the input 
impedance of the network (output impedance of the  tubes) to the load 
impedance at the resonant frequency. The output impedance of the tubes ( 
or the input impedance into the network) can vary depending on how hard 
you desire to work the tubes. The tubes are specified to work at a 
maximum but can be operated at less for longer life.

You work from the antenna back to the tube output.  Pick your antenna 
feedpoint impedance (50, 72, 450, 600) and work back to the tube output 
.  By decoupling the network you alter the ratio and can then reduce the 
load to the tubes or alter the ratio to feed different load impedances.

What I am saying here is that both sides of the network are varable and 
the coupling allows for adjustment over a limited range.
---
Ron