Well, I haven't been paying a lot of attention, so not sure what you're 
looking at as far as bias, if the bias current isn't staing the same, you 
would need to take a look at the actual voltabe on the grid of the tube 
itself.  If that voltage is changing, that would be why current is 
changing.  If that voltage stays the same, then tube is changing 
conduction.

101 was a totally different radio, I have a 101 still, thought I just had 
to have one a couple years ago as I use to have one, so bought one on 
ebay.  Like I needed another rradio...  I fired it up to make sure it 
worked and never put it on the air.  You really need to find some one who 
really is a damn good tech to solve this, as I said, measure grid voltage 
right on the tube, could be as simple as a bad bias pot.
73
Butch
WA0VJR
Node 3148
Wallace, ks.