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MD 1772LB (B1770NSL/T)
MEDION
5. Under override condition, “CHECK SIGNAL” will show up on the screen.
4-6 OSD (On Screen Display) Circuit
1. The I502 HTV021-02 is OSD IC. The OSD signals are worked by positive vertical pulse from I701 pin 32
that goes through R521 to I502 pin 10, and positive horizontal pulse from HFLB1 through R513 to I502
pin 5. CPU I701 pin 27, 28 (I
2
C bus) transfers information to I502 pin 7, 8.
2. The OSD R. G. B signals and blanking signal are terminated at I502 pin 15, 14, 13, and 12 to I501 pin 2,
3,4, and 1, then the OSD picture appears.
