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– 14 –

1

Confirm that the slider moves in direction 

C

 to move down

the chuck plate if the gear (LOAD 1) is rotated in direction 

A

 or

the chuck plate moves up and the slider moves in direction 

D

 if

the gear is rotated in direction 

B

.

chuck plate

slider

gear (LOAD 1) ass'y

A

B

C

D

– 15 –

This adjustments is necessary when the system controller (IC201),
variable resistor (RV201), slider (R), slider (L), or chassis (ELV)
was replaced for any repair.

Adjustment Method:
1. Connect this set to the master unit (e.g. MDX-C670/

C670RDS), load a disc magazine, and place the set vertically
as shown below.

2. Connect the regulated power supply to the master unit, and

turn the power on.

3. Press the DISC button on the master unit and select DISC 5.

4. At this time, if the elevator shaft does not position between

comb teeth A and B at addresses 5 and 6 as shown below,
adjust the following.

5. Press repeatedly the DISC + and – buttons on the master unit

so that the elevator shafts moves from address 6 to address 5,
or from 5 to 6. At this time, adjust RV201 on the main board
so that the elevator shaft positions smoothly between comb
teeth A and B.

6. Further, place the set horizontally and make same adjustment

as mentioned above.

7. After adjustment at addresses 5 to 6 is finished, check all op-

erations from addresses 1 to 10 with the set placed vertically
and horizontally respectively to confirm that the elevator shaft
positions in a range between comb teeth A to B.

power supply

GND

+

BUS cable

CDX-727

master unit

comb tooth at address 6

elevator shaft

comb tooth at address 6

comb tooth at address 5

RV201

OK

NG

elevator shaft

comb tooth at address 5

A

B

A

B

– 16 –

1.

Perform adjustments as given.

2.

Power supply voltage: DC14.4 V (more than 3A).

[RF  BOARD]  – Conductor Side –

Procedure:
1. Connect the oscilloscope to TP (RF) and TP (VC) on the RF

board.

2. Put the set into play mode by loading the disc.
3. Confirm that oscilloscope waveform is clear and check RF

signal level is correct or not.

Clear RF signal waveform means that the shape “≈” can be clearly distin-
guished at the center of the waveform.

[RF  BOARD]  – Conductor Side –

Procedure:
1. Connect the oscilloscope to BP11 (TE) and TP (VC) on the

RF board.

2. Put the set into play mode by loading the disc.
3. Press the 

= AMS + button, and check the traverse wave-

form*.

4. Confirm that the oscilloscope waveform is symmetrical on the

top and bottom in relation to 0 V dc, and check this level.

* Traverse waveform: This is the tracking error wave form appears

when crossing the track.

TP

(VC)

IC11

IC51

CNJ12

TP (RF)

oscilloscope

+
–

RF signal waveform

VOLT/DIV: 200 mV
TIME/DIV: 500 ns

level: 1.4 

±

 0.3 Vp-p

TP

(VC)

IC11

IC51

CNJ12

BP11

(TE)

oscilloscope

+
–

A

B 

0 V

A=B

traverse waveform
(100 track jump waveform)

VOLT/DIV : 500 mV
TIME/DIV : 2 ms
Center : 0 V

Traverse waveform

– 17 –

• FOCUS  GAIN  ADJUSTMENT
  (COARSE  ADJUSTMENT)
This adjustment is to be performed when replacing the following
parts.
• Optical Pick-up Block
• RV14

– Conductor Side –

Procedure:
1. Set RV14 (RF board) to the standard position.
2. Check that there is not an abnormal amount of operation noise

(white noise) from the 2-axis devise. If there is, turn RV14
slightly clockwise.

– Conductor Side –

The set does not play because of no focus operation.

Operation noise is heard due to a scratch or a dust, then opera-
tion will be unstable.

RV14

IC11

IC51

CNJ12

MIN side
(low gain)

MAX side
(high gain)

RV14 standard position