Aiwa NSX-D737 Service Manual page 40

ELECTRICAL ADJUSTMENT (CD)
CD NAIN C.B
SFR1 (TB) (&)
SFR2 (FB) (6)
ae
Note: Connect a probe (10:1) of the oscilloscope
and the counter to a test point.
1. VCO Frequency Adjustment
1) Connect the frequency counter to the test points
TP1 (VCO) and TP2 (VCO GND).
2) Set the test disc and PLAY mode.
3) Connect and short between TP3 (ASY) and TP4
(GND).
4) Adjust SFR4 so that the frequency counter
reading is 4.27MHz + 0.02MHz.
5) After the adjustment is completed, disconnect the
short lead wire.
2. Focus Bias Adjustment
Make the focus bias adjustment when replacing
and repairing the optical block.
Oscilloscope
(DC range)
CD MAIN C.B
TP5 (RF).
TP6 (VREF)
1) Connect an oscilloscope to the test points
TP5 (RF) and TP6 (VREF).
@ ©© 06,40
58
TP2 (GND) ©
TP1 (VCO)®
2)
SFR4_(VCO)
TP7 (TE)
¥ Ic2
SFR3 (TG) (©)
2) Turn on the power switch.
3) Insert the test disc TCD-782 (YEDS-18) and play
back the second composition.
4) Adjust SFR2 (FB) so that the RF waveform
must be maximum and clear.
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) Wa \ ) Wy () YY () N)
NW
ob'bss
XXX)
WKKRKARRKKY
MAX
VO00000.0 009
CLEAR
VOLT /DIV : 0.5V
TIME/DIV : 0.5 uS
. RF Waveform Check
This check should be performed whenever the opticd
block is replaced in repair.
1) Connect an oscilloscope to the test points TPS
(RF) and TP6 (VREF).
2) Turn on the power switch.
8) Insert the test disc TCD-782 (YEDS-18) and play
back the second composition.
4) Check that the waveform appears as shown in
the figure.