[NJARC] Atwater Kent 82 AVC Volume Problem

[George B. Shields, Jr.]

Hi All,
Well, I haven't been this totally flummoxed in quite along time!  I am still experiencing a huge amount of trouble with this AK82 volume and AVC control problem.  It is a very strange arrangement in which a type 224 tube is used ass a "control tube" to regulate both the volume and AVC functionality.  When the radio first powers up the volume comes on full blast regardless of position of the volume pot, then over the course of about 5 or 6 seconds lowers to a normal range.  After anywhere from a few minutes to maybe 15 or 20 minutes the volume will begin on its own to fluctuate WILDLY - some times jumping to full volume and back way down to the point where you need to turn up the volume pot to maybe 3/4 the way up and then it will fluctuate between louder and softer on it's own and then stabilize for awhile and then begin doing it all over again.  Frequently, the volume will fluctuate so rapidly it will actually flutter, going up and down several times a second!  I have replaced the control tube 4 times with no effect.  I have replaced EVERY SINGLE resistor and capacitor in the radio excepting for the wirewound resistors.  There are NO original resistors or caps functional in the set.  Every component is precisely on schematic spec. The volume control is original although it has been cleaned and measures steady.  I have noted that voltage across the resistor network of which the volume control is a part will at times fluctuate as much as 8-10 volts and I have been unable to figure out why.  The power transformer seems fine and gets only slightly warm after playing the set for the better part of an hour.
This radio was exhibiting this problem when I bought it.  It had been restored by someone else in the past who didd the capacitors but only a few of the resistors so of course I immediately replaced all of those remaining nasty ceramics.  But none of my work has had any effect whatsoever on this.
Now, my feeling is to disable to AVC functionality of this control tube circuit, however the usual tricks of grounding out either the grid or the screen does not work. That results in disa ling the volume control entirely with the radio playing only at full volume regardless of position of the volume control.  Im at a complete loss as to how to disable the AVC and yet retain volume control functionality!
The AK82 is notorious for this horrible and screwy volume  / AVC setup and I believe it's actually the only AK model out there that employs it, as other 1931 models did not have an AVC.  
Any of your guys who are way smarter than poor I ever experience this problem?  What suggestions can be offered to me to disable this AVC and make the radio volume stable and controllable??????  Any thoughts will be very much appreciated!  I also can shoot over a schematic to anyone who would like to have a look at it!
Many thanks guys,-George-
george-shields at msn.com