Rgb Cutoff - Sony CPD-420GS Training Manual

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RGB CUTOFF

The RGB Cutoff levels can only be adjusted via the DAS/CATS software
or by the Color Restoration function (explained later). IC1001 on the N
board, via the I 2 C data bus controls IC001 D/A outputs at pin 3 (R BKG),
pin 4 (G BKG) and pin 5 (B BKG). The D/A outputs from IC001 are input
to CUTOFF AMP IC004 pin 1 (B.IN), pin 3 (G.IN) and pin 4 (R.IN) which
sets the CRT Red, Green and Blue cathode DC cutoff level. The output
of IC004 pin 7 (R.CUT), pin 10 (G.CUT) and pin 13 (B.CUT) clamp the
CRT Red, Green and Blue cathodes. The +180V DC with pull-up resis-
tors R109, R209 and R309 and D106, D206 and D306 form the voltage
divider network for the R G B cutoffs respectively.