It looks as though I'll have to find equivalents for at least the 13301 and
13300 , 1969 vintage, from a JBL SA660 amp. One 13301 is leaky. Anyone have any data on these early power transistors, TO3 and T066. I should be able to determine Hfe and adjust to fit higher gain replacements-- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on
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