CDX-T70MX
SECTION 4
ELECTRICAL CHECK
Note:FOCUS BIAS CHECKTRACKING OFFSET CHECK
1. This check is performed with the set placed horizontally.
2. Power supply voltage: DC14.4 V (more than 3 A).
Connection:Connection:
3. Be sure to use the disc OYEDS-18� parts code: 3-702-101-01, but only
� RF Board (Component Side) �� RF Board (Component Side) �
when indicated.
4. Use a master unit that supports SONY bus system.
oscilloscopeoscilloscope
Connection:(AC range)(DC range)
power supply
++
(DC 14.4 V)
��
master unit
+
GND
TP (TE)
BUS cable
IC101IC101
TP (RFAC) TP (VC)TP (VC)
compact disc changer
Procedure:Procedure:
1. Connect the oscilloscope to TP (RFAC) and TP (VC) on the1. Connect the oscilloscope to TP (TE) and TP (VC) on the RF
RF board.board.
2. Put the set into play mode by loading the disc (YEDS-18).2. Put the set into play mode by loading the disc (YEDS-18).
3. Confirm that oscilloscope waveform is clear and check RF sig-3. Press the [ AMS ]. > button on the master unit, and check
nal level is correct or not.the traverse waveform*.
Note:4. Confirm that the oscilloscope waveform is symmetrical on the
Clear RF signal waveform means that the shape OE� can be clearly distin-top and bottom in relation to 0 V dc, and check this level.
guished at the center of the waveform.
* Traverse waveform: This is the tracking error wave form appears
when crossing the track.
RF signal waveformTraverse waveform
VOLT/DIV: 500 mV
VOLT/DIV: 200 mVTIME/DIV: 2 ms
TIME/DIV: 500 nsCenter: 0 V
(10 : 1 probe in use)
A
+ 0.3
level: 1.4 � 0.4 Vp-p0 V
B
A=B
traverse waveform
When observing the eye pattern, set the oscilloscope to AC range
(100 track jump waveform)
and raise the vertical sensitivity so that it may be easily seen.
1717 |
ACEC
