LG StudioWorks 570LE Service Manual page 21

4. NO RASTER (OSD IS DISPLAYED) – TDA8752BH / MX88L284
CHECK
OE(H-SYNC)?
U1 PIN87
YES
CHECK
CLAMP INPUT(H-SYNC)?
U1 PIN89
YES
CHECK
H-SYNC INPUT?
U5 PIN203
YES
CHECK
CLOCK INPUT
?
(25MHz-95MHz SINEWAVE)
U5 PIN207
NO
NO
NO
NO
- 20 -
CHECK H-SYNC LINE
(D-SUB U8 MICOM
U1 PIN95)
CHECK SIGNAL LINE
FROM U5 PIN11
TO U1 PIN89
CHECK SIGNAL LINE
FROM U2 PIN80
TO U5 PIN203
CHECK SIGNAL LINE
FROM U1 PIN84
TO U4 PIN254
(1024x768/85Hz : 95MHz)