AIWA BZG2 Repair Manual

CD ELECTRICAL MEASUREMENT
Y Perform the measurement after the machine enters the test mode.
Y Place the CD mechanism horizontally level.
Y Equipment and tools required
Measuring equipment: Oscilloscope (Use the probe of 10:1)
Digital Multimeter (Use it in the DC Volt range.)
Jitter meter (Kikusui 6235 or equivalent)
Test disc: TCD-782
ATD-001
1. RF Waveform Check
1) Connect an oscilloscope to test point (IC101 4pin, RF), (IC101 11pin, Vref).1.6 Vp-p
2) Play back the 2nd track of the TCD-782.OSCILLOSCOPE
0V
3) Check to see that the RF waveform has the maximum amplitudeEYE PATTERN
and the center of the wedge waveform has the clear blank.must be CLEAR and MAX.
OUTPUT
VOLT/DIV: 500mV
+ --
TIME/DIV: 0.5?S
RF
AC INPUT
2. Jitter CheckVREF
1) While an oscilloscope is kept connected in the same test pointOSCILLOSCOPE
as in the 2. RF Waveform Check, connect the output terminalJITTER METER
of an oscilloscope to the input terminal of a jitter meter.
OUTPUTINPUTns
2) Set the VOLT range selector of an oscilloscope to 500 mV
+ --
range or lower.
RF
3) Play back the 2nd track of the TCD-782.
VREF
4) Check to see that a jitter meter indicates 40.0 ns or less.
3. Tracking Balance Check
1) Connect an oscilloscope to test point (TE), (VREF).OSCILLOSCOPE
A
2) Play back the 2nd track of the TCD-782 and press the PAUSEVREF
B
button.
OUTPUT
3) Check to see that the traverse waveform on an oscilloscope isA=B
+ --
vertically symmetrical.
TEVOLT/DIV: 500mV
VREFTIME/DIV: 1mS
DC INPUT
4. Play-ability Check
1) Play back the 4th, 9th and 13th track of ATD-001. Check to see
that noise does not occur and sound skipping does not occur.
5. Laser Current Check
DIGITAL MULTIMETER
*Do not perform this measurement unless the laser is suspected to be
V
defective.+ --
1) Connect a Digital ultMimeter across the resistor R8 (3.3 ohms).
R8
2) Play back the TCD-782 and check the DC voltage value on a DigitalR8
Multimeter.
3) Calculate the laser current (Iop) by dividing the DC voltage acrossREXAMPLE
R8 by the resistor value.
Laser current (Iop) = DC voltage across R8 divided by the
J1171ZS
resistor value (3.3 ohms).
0009372
SPEC VALUE
37.2mA
-20-