Kristel 1428-30k series, Руководство по обслуживанию

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2. SYNCHRONOUS PROCESSING CIRCUIT
IC 801 circuit (WT8041), a sychronous signal processor of multi-sync, is capapble of many functions such as
the horizontal and vertical frequency discrimination, display mode selection and synchronous pulse polarity
detection. Pin 15 and pin 16 work as a clock generating circuit. Output pin 4 is active high while pin 5 is ac-
tive low, fixed polarity and have the same pulse width as the original horizontal and vertical sync. signal. Pin
7 works as a frequency discrimination which is active low. Pin 9 and 14 work as mode selector which controls
output. These output pins are to control Vsize, Hphase and Hosc of every display mode.
3 HORIZONTAL / VERTICAL PROCESSOR
The IC 601 is a combination horizontal and vertical processor.
The vertical SYNC is applied to pin 14 of IC601. Oscillation is determined by C306, R303 and C305. The
saw-tooth pulse generator built inside the IC can generate saw-tooth signal through a buffer stage to pin 15.
1428-30k series
pg. 12
to L502 / power supply
to R907 / FBT
to VR301
to R334 to R613
to FBT