[Clay3]

I bought this amp when it was new, 1979.  ( jc penney mcs series amp 3835 )
has been good to me but now has developed problems.
can't find a schematic for the thing or a parts list.
i think that a semiconductor has gone bad but can't cross ref.
the markings on it are [    d438   ]
                                      f-8g
 
any ideas out there?

 

[amb]

Search for 2SD438.