Change of circuit from triode to tetrode

[Tubelab_com]

I presume that these were 807's without the top cap.

All 807's had top caps. An 807 without the top cap is a 6L6GB (same guts inside).

 

[richard8976]

The way it is going on the ham forum, is to focus on some feedback around the 6L6 driver to the KT88's/807's. That would make things a tad better perhaps. That would represent keeping the triode connection. :c)