Orban OPTIMOD 8685, Operating Manual

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OPTIMOD MAINTENANCE
4-3
F) Disconnect the power cable assembly from J801 of the DSP board.
G) Remove the six Phillips screws holding the DSP board to the bottom of the
chassis.
H) Remove the DSP board.
4. Removing the Front Panel.
To service the headphone amplifier, the color LCD display, the pushbuttons, or
the rotary encoder, it is first necessary to remove the front panel assembly.
A) Make sure that AC power is disconnected from the 8685.
B) Release the catch on J200 on the display interface board and remove the rib-
bon cable from J200.
C) Remove the cable assembly that connects through the chassis bulkhead to the
headphone amplifier board.
D) Remove the six Phillips head screws that hold the front panel to the main
chassis.
These are located in two groups of three on the sides of the main chassis,
close to the front panel.
E) Pull the front panel toward you to remove it.
Do not stress the cables connecting the front panel to the main chassis.
To protect the assembly from cosmetic damage, set it down on a soft sur-
face like foam rubber, a quilt, or a blanket.
5. Removing the Headphone Amplifier Board.
Because they are socketed, you can remove and replace the headphone amplifier
driver chips without further disassembly.
If you need to remove the headphone amplifier circuit board (to access compo-
nents other than the headphone amplifier driver chip):
A) Make sure that AC power is disconnected from the 8685.
B) Pull the friction-fit knob off the headphone volume control.
C) Remove three Phillips screws.
This will free the board.
6. Preparing to Remove the Rotary Encoder Board.
The circuit board containing the pushbuttons, joystick, and rotary encoder is
mounted on a metal shield plate. To remove the plate, remove three screws and
lift the plate off at a 45-degree angle, following the axis of the rotary encoder.