Xvm-R75 - Powering The Backlight - Sony XM-1502SX Training Manual

Motor Drive – With power applied to the unit, pressing the Open / Close button is recognized by U505/pin 44
(HIGH). U505 checks the state of the limit switches to determine if the panel is open or closed and rotates the
motor in one direction or another by outputting a HIGH at either pin 21 (forward) or 23 (backward). The motor
continues until the limit switch closes to stop the motor.
If the panel close switch was closed (ground at B9), Syscon U505/pin 30 outputs a pulse to unlatch the panel
permitting the motor to lower the panel. The motor drives a series of gears. The larger white gear shown in
Figure 3-16 contains a slip clutch to prevent damage if the panel were stopped. If either limit switch were
defective, the motor would run continuously, eventually damaging the motor drive IC U8.
XVM-R75 – Powering the Backlight
The display's backlight can be removed and powered independent of the main board. See Figure 3-17 and apply
8 to 12Vdc to the two places shown:
•
Fuse F3
•
Connector B1/pin 1
•
Ground to pin 8 of HV transformer (near the end of the board)
Figure 3-16
Figure 3-17 - Powering the Backlight
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