From: phil_a@tpg.com.au   
      
      
      
      
   > UBT-1 is rated at 160mA on the primary...   
      
      
   ** Yep -  the total idle current is 110mA.   
      
      
   > Did those 300Bs develope a dead short?   
      
      
   ** According to the owner/builder -  there was a flash / bang / wallop event   
   and then a dead channel.   
      
   One dud 300B draws no bias current while the other draws waaaay to much, the   
   UBT-1 has an open deep inside but shows no sign of shorted turns.   
      
   What has me intrigued, however, is the low THD figures at and near full   
   power PLUS the fact that 3H dominates.   
      
   The test results are far more like a PP class A triode amp than a SE one.   
      
   The 6SN7 is running at full gain ( about 18 times per half ) and there is   
   definitely NO negative feed back - in fact the two speaker windings have   
   been left floating.   
      
      
      
   ....  Phil   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)