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re: output tranny diode protection mod


 
9/29/1999 10:36 AM
Dai Hirokawa
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re: output tranny diode protection mod
For the "reverse-biased diode(s) from plate to ground on ea. push-pull side" output transformer protection mod, would it be sensible or stupid to add a fuse on the ground side? My thinking is that this would open the connection if ever the diodes went south. Thanks for any opinions bestowed.  
 
Dai Hirokawa  
 
9/29/1999 2:28 PM
Bruce
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Hmmm...to do what Dai, protect the 15 cent diodes? :>)  
Once they go, they usually stay shorted and if the OT is fused on it's center tap DC feeder, that fuse will probably blow pretty quick.  
The problem is, all the DC voltage (B+) is shunted to ground through the shorted diodes and that means high current through the OT until the center tap fuse blows.  
 
Bruce
 
 
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9/30/1999 3:28 PM
Dai Hirokawa
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Thanks for the reply Bruce! I gather that the protection mod itself (the diodes) are a bad idea. Oh well. What do you think of small caps from ea. plate to ground? I sometimes see this and it looks to me like another protection mod.  
 
Dai Hirokawa
 
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