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Help with crazy modded ST-70 reversal. Again…

rudedogg said:
Hey guys. Another quick question: I added the “Yellow Paper” mod. This amp did eat rectifiers, most likely due to the excessive added capacitance in the PS, and modern tubes. Will this help with using modern manufacture rectifiers over old Mullard or Amperex parts? I know there has been much discussion on this mod and other options. Thoughts with just the original yellow paper idea?
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Yes. It will block "reverse current" in the GZ34 that occurs when the rectifier is overloaded. Best is to limit first cap to 60uF
 
Or, ditch the 5AR4 for a SS rectifier all together. I even left the yellow sheet mod in place. I've had the Weber WZ68 SS rectifier in for a week now and its worked out great. No more worrying about another 5AR4 failing. You do want at leased 500v caps in the amp though.
 

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Sometimes slightly loosening the tranfo nuts can quiet the vibration. Same with the chassis screws.
 
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