[Amps] Tetrode tuneup

[Bill Coleman N2BC]

Adding a "tune" mode to an AM RF PA with a pair of 4-400s.   What's 
better...  floating the screens or grounding the screens.  Does it matter?

To round out the picture:  no bias supply (grid leak bias only),  screen E 
derived via dropping R from plate B+

I have a relay that will easily handle the screen voltage and plan to switch 
in a suitable R in place of the screens to keep the voltage coming into the 
RF deck near normal screen value. I don't foresee it ever being 'hot 
switched' - It probably wouldn't last too many cycles at 3KV.  I don't want 
to mess with a clamp tube.

THX & 73, Bill   N2BC