Kurzweil PC3x, Руководство по обслуживанию

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Disassembly/Assembly
Top Enclosure
3-13
Removing the LCD Board
1. Follow the procedure described on page 3-8 to remove the enclosure support wall.
2. Follow the procedure described on page 3-9 to remove the Connector Board.
3. Disconnect the fl at ribbon cable from J15 on the Engine Board. This cable is bundled with
other cables routed along the rear panel portion of the top enclosure. They are secured
with tie wraps to cable mounts. Removing the LCD requires cutting the tie wraps and
separating the
fl at ribbon cable from the other cables routed along the rear panel.
4. The LCD is mounted onto a bezel that is secured to the Front Panel Board. Remove the
four screws that secure the LCD to the front panel bezel.
Figure 3-12 J203-1 and J203-2 connections on Front Panel Board
5. Refer to Figure 5. A two-wire soldered cable connects the LCD to J203-1 and J203-2 on the
Front Panel Board. These cables are not labeled at the Factory and the colors of the wires
attached to the LCD may vary. Polarity is important! Before you desolder the wires, mark
one of them with a designation such as a black line to avoid reversing the wires when they
are resoldered.
Caution : 1000V high frequency voltage present, which can cause burns–be sure power is off!
6. Desolder the wire connections at J203-1 and J203-2 on the Front Panel Board. Lift the LCD
Board up and remove it.
J203-2 RETURN BLACK
J203-1 HOT BLUE
LCD