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(B) Tracking Adjustment   
 

i.   Connect oscilloscope to the test point TP3 (KA9220C) and Vref (J6).
ii.  Press PLAY button and adjust VR4 to maximum and press SKIP DOWN button  to

make it Tracking off.

iii.  Adjust VR2 to get symmetrical waveform height. After adjust VR4 to center.
iv.  The result is show as below fig. 2

FL8550

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Connection point

Settings

      State

Adjustment Location

U1 (KA9220C)
Pin 57 (R11)
Pin 56 (R12)
See fig 3

1. Oscilloscope Probe: x 10
2. Oscilloscope setting

CH1: 20mV/division
CH2: 10mV/division

Remark: X-Y mode

Play State

Adjustment VR3

i. 

Set the frequency generator output to 1KHz and 100mv.

ii.  Press the play key and press skip key to move the pickup to halfway across the disk
       (R=35mm).
iii.  Adjustment VR3(focus gain) so that the Lissajous waveform is symmetrical

above the X axis and the Y axis.

Fig. 3

Higher gain

Optimum gain

Lower gain

FL8550

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   Connections point

Settings

State

Adjustment location

U1 (KA9220C)
Pin 53 (R13)
Pin 52 (R14)
See fig.4

1. Oscilloscope probe: X10
3. Oscilloscope setting

CH1: 50mV/division
CH2: 20mV/division

Remark: X-Y mode

Play State

Adjustment VR4

i. 

Set the frequency generator output to 1KHz and 100mV.

ii.  Press the play key and press skip key to move the pickup to halfway across the disk
       (R=35mm).
iii.  Adjustment VR4(track gain) so that the Lissajous waveform is symmetrical above

the X axis Y axis.

Fig 4

                          Higher gain

   Optimum gain

                Lower gain

Vref

FL8550

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FL8550

1.  3346 CD Player Evaluating Filter x 2 (NF Electronic Instrument)

2.  VP7722 Panasonic Audio Analyzer

3.  Sony YEDS18 Test CD disc

1.  The audio output of the CD player under test is connected to the CD filter L

& R inputs.

2.  The outputs from the filter are connected to the Audio Analyzer.

1.  Set the mode of the filter to ‘ THRU’

2.  Set the mode of Audio Analyzer to ‘ LEVEL’  mode

3.  Select track 2 of the test disc and play the CD disc

4.  The output voltage and gain of the R & L channels are taken by pressing

the respective buttons on the control board of Audio Analyzer.

1.  Set the mode of the filter to reference level mode.

2.  Select the track 3, 4, 5, and 6 of the test disc and run it under ‘ Play’  mode.

3.  Check the output of the R & L Channels

1.  Set the mode of the filter to ‘ DIST/CH-SP’  mode

2.  Set the audio analyzer to ‘ DIST’  mode.

3.  Set the unit of the audio analyzer to ‘ %’  mode

4.  Select the track 2, 4, and 5 on the test disc and run them under ‘ PLAY’

mode

5. Check the % of each R & L channels

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