Here I have started work on the left channel output board. I have replaced one resistor (upper right
next to the [bad] driver transistor), and pulled the emitter resistors. You can see the extent of the
damage...
Smoked....
Strange... resistor was still
good, but the ceramic
insulation had fallen off. I
found several like this on
other boards as well.
These are the cracked
emitter resistors. These
are known as "Metal Plate"
resistors. It seems to be a
common failure in  E-202's.
I have seen three units
with this same failure. I  
suspect these are the
cause of the original melt
down. I think the (original)
component  may have
been a bit under rated
(3W) for the job and was
prone to failure over time.

My theory goes like this:  
The ceramic jacket
stresses with heating and
cooling and finally cracks
and chips. Once the metal
plate is exposed it loses its
ability to dissipate heat
and starts to "cook", until it
fails.

The originals are 3W. I
have a brand new set of
KOA 5W replacements
Installed on both boards.

Generally, I always make
the same change to both
sides of the amp... what is
done to one side, is done
to the other.  This is to
ensure that there is a
components to component
match across each
channel.
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