No steel wool... You don't want that stuff around electronic components
or circuit board.
Usually the contact in those TO-3 sockets are real good.... just unplugging
and then re-plugging in the transistor will be all that is needed. For
clean up use contact cleaner or in the worst case a pencil eraser to remove
oxidation and then contact cleaner.
My best advice.... if it's not broken, don't fix it. This would not be
the cause of humming.
--
Best Regards,
Daniel Sofie
Electronics Supply & Repair
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"bigtom" wrote in message
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marantz amplifier PM-84

the output transistors are screwed to a big aluminum heatsink.
the transistor terminals are not soldered but simply push into sockets.
i was thinking of cleaning the terminals with some steel wool
then spraying the sockets with contact cleaner for a better
connection. is this a good idea? are there better alternatives?

the original problem was humming(a couple of high esr caps and some
dry joints)