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7. Convergence
Now for the convergence board. This board is very well designed, with only
one exception, yep, they used the same little Mickey mouse resistors on this
board. The early version boards had one each, while the later version boards had
a double stack. There are twelve of them on the convergence board (24/stacked on
the later version). R118, R117, R218, R217, R318, R317, R418, R417, R518, R517,
R618 and R617. There are also 48 1.2 ohm (same Mickey-mouse resistors) right
near the power transistors.
And while you have this board out, make sure you solder the many leads for the
30 power transistors that are heat-sinked. If you look very closely at the
contacts on these transistors you should see the need for soldering, especially
on a high use projector, take your time and solder all 90 contacts.
Next, you'll want to clean that heat sink surface insulator (denatured
alcohol) and apply a very light film of petroleum jelly on that insulator.
Before reinserting the board, use a ruler or other flat device and align each
transistor so that each one would be perfectly inline with the heatsink surface.
Now take each heat sink clamp and bend back for better tension.
Do the same for the vertical and stigmator boards (if it has stigmator
board).
8. Contrast Correction Module
Remove the contrast modulation board (color correction module), right next to
the ACON board (above the control module). This module is not in all Marquee's,
look for it on the 8500, 8500LC. 9000, 9500LC.
This board will allow color correction in nine different zones. Much needed
for multi-display commercial systems for edge matching and such, but not needed
in video applications, and could effect the overall purity of the image – REMOVE
IT!
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