Service manual

16
H. sync., V. sync feed from IA01 pin41,42 to I301 pin1 ,2. When the H. Freq. is over 110kHz or
below 30kHz, I301 will shut down to protect the Horizon. output CKT from being damaged. The
Horizon. oscillator is build by C303 and R301 and determine the Horizon. frequency range.
C304, C305, R302 build up PLL 1 loop filter,
Via Icon, the IIC-bus allows a linear adjustment of the Horizon. position by comparing
relative phase of horizontal Sync. and oscillator saw-tooth(in PLL 1 loop) and feedback from
Horizon. output stage.
and correction of pin unbalance and parallelogram are done by modulating the
phase between oscillator saw-tooth and horizontal. flyback (in loop PLL2)
The PLL2 phase detector is similar to PLL 1 detector and compares the Horizon. flyback pulse
at pin 12 with the oscillator saw-tooth wave-form. The controlled currents are independent of
Horizon. freq. The PLL 2 thus compensates for the delay in the output horizontal deflection CKT
by adjusting the phase of the HDRV (pin26) output pulse.
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