Advertisement
RG-M10BU
!Adjustment Procedures
I
•
Before the adjustment
The initial screen ( that is a comment "Put a disc on the turntable" ) is displayed when the
power supply 'is turned on without a disc.
The screen shifts to the control screen after reading a disc if a disc is set and the door close
detection switch is pressed. The disc keeps rotating for approximately 1 minute after shifting
to
the control screen. Press the playback and then the st-0p button if you want to stop the rotation.
With a disc on the turntable, the screen shifts
W
the c-0ntrol screen quickly after reading a TOC
when the power supply is turned on. (The initial screen is displayed while TOC is being read.)
• Adjustment measure
Oscilloscope , Test disc (CRG-1117)
•
Procedures
1) FE (focus error) bias (CD stop mode)
CC· Connect an oscilloscope between TP501 pin2 (FE) and TP501 pin9 (
OND).
(?i
Adjust R508 so that the DC voltage of the focus error signal becomes O±lOmV.
2)
EF
balance
0~
Connect TP501 pin6 (TEST) with TP501pin7 (
GND).
a;.
Connect a oscilloscope between TP501 pin4 (TE) and TP501 pin8 ( VC) and play the test disc.
' : i' D
Adjust R510 so that the center voltage of the waveform becomes 0±0.05V.
3)
Gain adjustment
If the gain is out of adjustment, the symptoms below will appear.
Focus is not obtained and disc does not rotate.
e
Gain too low
Focus gain
Tracking gain
Mechanical shock occurs easily and sound is interrupted.
Or
time counter display
stops counting.
eGain too high
Focus gain
Tracking gain
Scratches (on the disc) easily interrupt play, and noise is increased during play.
Since the follow-up ability of the pickup is too high, the pickup may oscillate and
oscillating sound may output.
As described above, the focus and tracking gain
adjustment are performed
to
satisfy mutually
contradictory characteristics.
A simplified adjustment procedure is described below.
However, since exact adjustment can not be performed
prior to adjustments, note( or mark) the positions of the
semi-fixed resistors.
If the positions after the adjustment are only
different, return the VRs to their original position.
Focus
gain
adjustment
1. Connect an oscilloscope to TP 501 pin(FE) and
TP 501 pin8 ( VC ).
2. Load the test disc and press the PLAY button.
3. Adjust R522
CF.GAIN
ADJ.)
S-O
that the correct
waveform as shown in figure 1 is obtain.
1~38
(No.20478}
Focus Gain Adjustment
100rnV
I
div.
2ms/div.
Fig. 1
vc
Advertisement
