Aiwa XR-EM52 Service Manual page 56

3.TRACKING BALANCE CHECK
1) Connect the TE and Vref to the oscilloscope.
2) Playback the second track of TCD-782 and press the PAUSE button.
3) Check that the traverse waveforms of oscilloscope are up and down symmetrical.
d
4. PLAY ABILITY CHECK
rd
1) Play back the 3 , 8
p
occur.
5.LASER CURRENT CHECK
*Do not perform this measurement unless the laser is suspected to be defective.
1) Connect digital multi-meter across the resistor R8A (3.3ohm).
2) Play back the TCD-782 and check the DC voltage value on the digital multi-meter.
3) Calculate the laser current (Iop) by dividing the DC voltage across R8A by the
resistor value (R8A= 3.3ohm).
Check that the laser current (Iop) is SPEC value
t
A = B
th th
and 13 track of ATD-001. Check that the noise does not occur sound skipping does not
r
A
0V
B
VOLT / DIV: 100mV
TIME / DIV: 1ms
10%.
– 56 –
OSCILLOSCOPE
u
TE
Vref
a
DIGITAL MULTIMETER
R8A
R8A
EXAMPLE
KSS -213F
05Y93
DA372
o
OUTPUT
V
SPEC VALUE
37.2mA