[Amps] IM distortion and such

[Gudguyham at aol.com]

In a message dated 6/28/2006 10:21:16 AM Eastern Daylight Time,  
W4EF at dellroy.com writes:


BTW,  TWTA linearizers actually exploit this phenomenon to reduce
overall IMD.  Sometimes two wrongs do make a right :)

73, Mike W4EF  




I think this whole thread started out when a posted claimed that he was  
getting 1800 watts out of an Ameritron AL-1200 with a 100 watts of drive, then  
continued to say "additional output could be anticipated with drive up to 130  
watts".  I don't think with all the hoopla we ever did determine "if in  fact" 
one would see more power out from the 3CX1200A7 when driven with up to 130  
watts.  The Ameritron AL-1200 manual does state that the maximum drive  
"permissible" for the Al-1200 is 130 watts.  So, what does this all mean in  the real 
world?  One posted claimed that the emission of a 3CX1200A7   falls off at 85 
watts. Does it?  The Henry 5K uses a pair of 3CX1200A7's (I  had one) I saw 
3500 watts output with 100 watts drive.  Assuming 130 watts  of drive 
"permissible" per tube, then 260 watts of drive for a pair should yield  some major 
power.  I never drove mine past 100 watts since that was all the  driving power I 
have.  With my AL-1200 it continues to make power up to 100  watts drive I 
don't know what it will do with more drive, but perhaps someone  knows.  So I 
guess the question is Why does Amerritron say you can drive  the tube with up to 
130 watts?  And, if one does do that, is that  "overdriving it"??  With all 
things being equal I think my 100 watts RF is  the same as anybody elses 
(strickly speaking) and not considering  cleanliness.
Since I do not have 130 watts available I don't know just what would  happen. 
Does anybody?
Lou