[AMPS] 572B Rejuvenating ?

[Rich Measures]

>
>Anyone have experience with these tubes?
>I picked up a SB-200 thru Packet that was " mint, works great, etc". 
>Damn thing barely makes 350W out, and looks like it was in a tobacco
>barn.
>I have cooked the filaments for 1.5 hours at 15% overvoltage and picked
>up about 50W per tube. Do I dare leave the overvoltage run overnight, etc
>or go higher in voltage, or what ???
>
15% over-Voltage cuts the emissive life to under 1%,  Carl  If a pair of 
good tubes brings the output up to what you consider normal, maybe it's 
Trashtime?  I had no luck with the fil. overvoltage "rejuvenation".  A 
tube rebuilder told me that it only works if the tube was operated with 
too little fil. V for an extended period.  In a SB-200 this seems 
unlikely.
-  later


Rich. Measures.  Web site:  www.vcnet.com/measures


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