[AMPS] Re:(AMPS) sb-200 troubles

[William L. Fuqua III]

This is more than just a safety choke. With out it the 
small leakage current thru the Plate blocking capacitor would
would charge up the output capacitor to full plate DC voltage on 
top of which will be the RF peak voltage. This can cause the 
output loading capacitor to arc over.

   Even if the plate blocking capacitor had no leakage there would
be some DC across the output capacitance. This is due to the charging of the
blocking capacitor thru the pi network capacitors when the B+ is turned
on.
 
   If you suspect the "safety choke" don't simply remove it thinking it
is only there to protect equipment from failure of the plate blocking capacitor.

73
Bill wa4lav




  William L. Fuqua III  P.E.  E-mail WLFUQU00@POP.UKY.EDU  Phone (606) 257-4155
  Department of Physics and Astronomy      CP-177 Chem. Phys. Bldg.  
  University of Kentucky ,                 Lexington, Ky 40506-0055
 
  


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