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Mark Zacharias[_2_] Mark Zacharias[_2_] is offline
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Default Samsung model HL84676S

wrote in message
...
The customer phoned for a service call on this set. He says that he
has what
he describes as little specks on the screen. He says its like looking
at the
stars at night if this makes any sense. I'm trying to determine if
this is
repairable in the home or if I should have him bring it in. Does
anyone have
any ideas about these strange symptoms from what I've tried to
describe?
Thanks, Lenny



Here is some info from a co-worker:

"On this set, you get lucky. Very lucky. Not only is the DLP chip available
seperately, it can be replaced without disturbing the "tilt" adjustment.
Here's how.



Once you have the innards of the set naked, disconnect the cables going to
the mainboard and power supply. These will be the computer style connector
to the right of the fan and the longest multipin connector at the top left
of the DMD board. You can follow these and see. The 3rd connector here goes
to the ballast and has a brown and blue wire. Slide the engine out about 1/2
way.



Disconnect the rest of the connectors from the top left of the DMD board and
remove the fan. You will notice a couple of connectors on the right side of
the DMD board entering the top. These do not need to be removed for this
procedure.



With the fan out of the way you can work on peeling away the DMD proper.
Start by removing the 4 yellow short self tapping screws in the far corders
of the DMD assembly. These hold the shield over the assembly.



After you get the shield off, you will notice 3 white plastic caps on the
shield that reveal 3 yellow screws. Go out of your way NOT to disturb these,
unless you are a contortionist and wish to spend a lot of time resetting the
"tilt" adjustment when you're done.



You will also notice a large heat sink that was sticking through the shield.
This is attached to a die cast base that holds everything together with 8
silver screws, 4 with springs and 4 without. THESE you will undo. When they
are out, remove the die cast base and heat sink as a unit. There is no need
to seperate these.



You can now remove the DMD board, but do so as if hinged at the top. This
way you don't injure what's still connected at the top right of the DMD
board. The DLP chip is on the other side of the DMD board and is socketed.
Pay attention to which corner is beveled. With the new DLP chip in place,
the DMD board will sort of "snap" in place.



To steal a phrase from the Chilton's manuals, reassembly is the reverse of
dissassembly.



The new DLP chip will not require any value tweakings in the servicer's
menus."





Thanks to John at Electronic Wizards - Wichita, KS.



Mark Z.