CMT-M100MD, HCD-M10 - Sony Audio Service Manual (repair manual). Page 28

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Note :

1. CD Block is basically designed to operate without adjustment.

Therefore, check each item in order given.

2. Use YEDS-18 disc (3-702-101-01) unless otherwise indicated.
3. Use an oscilloscope with more than 10M

Ω

 impedance.

4. Clean the object lens by an applicator with neutral detergent

when the signal level is low than specified value with the
following checks.

Procedure :
1. Connect oscilloscope to TP (RFAC).
2. Turn the power on.
3. Load a disc (YEDS-18) and playback.
4. 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 distinguished at the center of the waveform.

Procedure:
1. Connect oscilloscope to TP (TE) and TP (DVC 1.65V).
2. Turn the power on.
3. Load a disc (YEDS-18) and playback the number five track.
4. Press the  u  button. (Becomes the 1track jump mode.)
5. Confirm that the level B and A (DC voltage) on the oscilloscope

waveform.

Specification level:      

                x

 100=less than 

±

22%

TP(RFAC)

TP(DVC 1.65V)

CD BOARD

oscilloscope

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

level : 1.1 

±

 0.3Vp-p 

CD BOARD

Oscilloscope

TP(TE)

TP(DVC 1.65V)

0V

Center of
waveform

B

Symmetry

A (DC voltage)

B=1.3 

±

0.6Vp-p

1. Press  FUNCTION  button to select ANALOG IN.
2. Insert a tape into deck, press the  z TAPE  button, and then press

the  X  TAPE   button to start recording.

3. Mode: Record

4. Mode: Playback

5. The playback output  level should be –2 

±

4 dBs (60 Hz),

–1 

±

4 dBs (8 kHz) and –3 

±

4 dBs (10 kHz) compared with 315Hz

playback level.

AF OSC

     PJ301
ANALOG IN
1) 315 Hz
2) 60 Hz
3) 5 kHz
4) 10 kHz

blank tape
CS-123

set

attenuator

600 

Ω

109 mV (–17 dB)

recorded
position

level meter

set

32 

Ω

J301
 PHONES

1.3

±

0.6Vp-p

 A