From: phil_a@tpg.com.au   
      
   "Phil Allison"   
      
   >   
   > ** More testing with the FFT feature on a Rigol scope:   
   >   
   > 3H is dominant from about 9 watts through to 21 watts.   
   >   
   > From 1watt to 4 watts, 2H dominates, then 4H, then 3H.   
   >   
   > If load R is changed to 16 ohms, 2H dominates all the way.   
   >   
   > 2H cancellation is occurring over a fairly wide range, but it is not   
   > complete.   
   >   
   > I can swap the 6SN7 with almost no change.   
   >   
      
   ** One final test result:   
      
   300Bs removed, 10:1 scope probe on grid pin, input 260mV rms to 6SN7.   
      
   2H  =  -24 dB  =  6%   
      
   3H  =  -42dB  =  0.8 %.   
      
      
   ....  Phil   
      
   --- SoupGate-Win32 v1.05   
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