Pioneer XR-P340M P74,.M. XR-P64OM, XR-P34OM xR-P74, XR-P64J--, XR-P34O, CHl, CHz, YEDS-7

)(F..P74(,.M. XR-P64OM, XR-P34OM xR-P74(), XR-P64{J--, XR-P34O

!Focus Servo Loop Gain Adjustment

o Objective

oSymptom when out of adjustment

oMeasurement Instrument Connections

lProcedurel

To optimize the focus servo loop gain.

Playback does not start or focus actuator noisy.

See Fig. 4.	o	Player State	Test mode,play
ISettings]	o	Adjustment Location	vR8152(FCSGAN)
cHl
20mY/division	a	Disc	YEDS-7
X-Y mode
CHz
5mVzldivision

1. Set the AF generator output to t.2kLlz and lVp-p.

2 . PresstheMANUAL/TRACKSEARcHFwD>> . >>!keyorREV!<< . << ￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿

halfwayacrossthedisc(R:35mm),thenpresst}reDOLBYNRkey,thePLAY/PAUSE >/D]key twiceinthatorder

to close the corresponding servos and put the player into play mode.

3. Adjust VR8152 (FCS GAN) so that the Lissajous waveform is symmetrical about the X axis and the Y axis.

( 1 0 : 1 )

Pin5{FOIN}

Pin4 (GND)

1.2kHz

1V p - p

Pin6 (FOER)

Fis.4

Focus Gain Adjustment

ffi ffi,

HighergainOptimumgainLower gain

1 - 3 6