[Kenwood] TS520S bad finals?

[Lou]

I am having trouble tuning my rig.  The plate current at startup needs 
to be adjusted via the bias control because it will not stay at 60ma, it 
is either 10ma low or 10ma high.  When I adjust it and go through the 
tune-up procedure and dip the plate I notice the plate current will be 
around 70ma or so.  Completing the tune up for maximum deflection shoots 
it off the scale when this occurs.  It seems to tune up fine for 40 and 
80 meters but not for the higher bands.  I suspect my tubes are failing, 
any comments?  Thanks
K8UPA
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