CMT-GP5, HCD-GP5 - Sony Audio Service Manual (repair manual). Page 16

16

Procedure:
1.

Connect an oscilloscpe to test point TP (TE) and TP (DVC) on
the CD board.

2.

AC is put in pushing  CD 

u

  button.

3.

FL tube carries out all lights and goes into CD test mode.

4.

Put the disc (YEDS-18) in to playback the number five track.

5.

Press the  CD 

u

  button.  (The tracking servo and the sledding

servo are turned OFF)

6.

Check the level B of the oscilliscope's waveform and the A
(DC voltage) of the center of the Traverse waveform.
Confirm the following :
A/B x 100 = less than ± 22%

Traverse Waveform

7.

Press the  CD 

u

  button. (The tracking servo and sledding

servo are turned ON)
Confirm the C (DC voltage) is almost equal to the A (DC
voltage) is step 4.

8. To exit from this mode, turn the power off.

• Always move the optical pick-up to most inside track when

exiting from this mode. Otherwise, a disc will not be unloaded.

• Do not run the sled motor excessively, otherwise the gear can

be chipped.

Traverse Waveform

Checking Location: CD board (Conductor side)

+
–

CD board

TP (TE)

TP (DVC)

oscilloscope

0V

B

level: 1.15 

±

 0.5 Vp-p

Center of 
the waveform

A (DC 

voltage)

0V

Tracking servo

Sled servo

ON

C (DC 
voltage)

Tracking servo

Sled servo

OFF

TP (VC)

TP (FE)

TP (TE)

TP

 (RFDC)

TP

 (DVC)

TP

 (RFAC)

IC103

IC101