[Boatanchors] Viking II Modulation Problem

[Richard W. Solomon]

I decided a scope would help in tracking down why I
have low modulation levels.
Surprise !! Looking at the Plate and Screen of the
second audio stage I get a high level of oscillation
as I crank the Gain Pot past about 4 on the dial.
I don't see any oscillation on the Grid ??

This is the stock Viking II audio circuit, no mods
made except to replace the caps.

Maybe I should bypass the screen of the second stage ??

Any thoughts ??

73, Dick, W1KSZ