Cramolin, AKA DeOxit.

Leonard

"bigtom" wrote in message
...
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)

marantz amp transistors
 

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)

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
...
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)

sofie wrote:
: 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.

Agreed.

The TO-3 leads typically are plated or tinned. Using an abrasive on them
may reveal a more-readily oxidizable metal in the core of the transistor
lead.

b.