KL7UW
HF 300W Power Amp



  I have a kit consisting of a pc board and parts marketed by Communications-Concepts, Inc.  
  Info: 
  
  Photos:
   
 
 
 
 
 
 
 
 
 
 
 

    
  
  • Kit before assembly
    •    
  • Assembled Amplifier

  Testing with a bench power supply at 28v currrent limited to 3 amps, results in 18w output with less than 1w input.  
  Setting Bias to 0.680vdc with zero drive results in 180ma idle current (zero drive) on the MRF-422's).
  My K3 was able to produce a max of 12w for drive.  Higher output likely with drive up to 18w.
 
  Testing using the 28v-20amp PS:  
 




RF TEST DATA


 BAND 
 DRIVE(W) 
 OUTPUT(W) 
 Ic(A) 
 Vc(V) 
 BIAS(V) 
 GAIN(DB)


 


 160M 
 12.0
 150
 12.0
 27.0
  X.XX
 11.0




  80M 
 12.0
 170
 14.0
 27.0
  X.XX
 11.5

 


  40M 
  6.0
 100
 10.0
 27.0
  X.XX
 12.2




  40M 
 12.0
 190
 16.0
 27.0
 0.715
 12.0

 


  20M 
  6.0
 130
 12.0
 27.0
 0.669
 13.4




  20M 
 12.0
 270
 17.0
 27.0
 0.698
 13.5

 


  15M 
 12.0
 270
 17.0
 27.0
  X.XX
 13.5

 


  10M 
   6.0
 180
 14.0
 27.0
  X.XX
 14.8




  10M 
 12.0
 240
 17.0
 27.0
  X.XX
 13.0

 

 



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