Casio QV-770, Руководство по обслуживанию

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VCC3, VCC5 voltage check PCB-LA
• Voltage supply
CP151 = 5.0
±
0.05 V.
(You can use an AC adaptor however, for the checking after repairs, apply above mentioned voltages.)
(1) Apply 5.0
±
0.05 V to CP150.
(2) Make sure VCC3 (CP160) is 3.3
±
0.1 V and VCC5 (CP152) is 5.0
±
0.15 V.
VCC2 adjustment and VCC7, VCC8, VEE2 voltage check
• Voltage supply
VCL0(CP101)=5.0
±
0.05V.
(You can use an AC adaptor however, for the checking after repairs, apply above mentioned voltages.)
(1) Apply 5.0 V
±
0.05 V to VCL0 and adjust VR100 so that VCC2 will be 5.0
±
0.02 V.
Notes: • VCC7 = 7.3 ~ 8.3 [V], VCC8 = 12.0 ~ 14.0 [V]
• VEE2 = –12.3 ~ –16.7 [V]
In addition, disconnect the power and make sure all output voltages are 0 V.
VCO free run frequency adjustment
• Voltage supply
VCC2=5 V
±
0.05 (V) (CP181).
VCC8 = 13.5
±
0.05 (V) (CP180).
VEE2 = –15.0
±
0.05 (V) (CP182).
Connect CP705 (CSY) and CP700 (GNP).
(You can use an AC adaptor however, for the checking after repairs, apply above mentioned voltages.)
(1) Monitoring CP710 (HDB) with a frequency counter, adjust VR720 so that the frequency will be 15.734
±
0.1 [KHz].
Notes: • Disconnect CP705 and CP700, then connect PCB-LA and make sure CP705 (CSY) and CP710
(HDB) are synchronized.
• Keep room temperature at 20
±
10
°
C.
PCB-LB
(CP710)
(CP705)
CS
VEE2
CSY
oscilloscope
frequency
counter
CSY
HDB
PCB-LA
(CP705)
PCB assy
(CP181)
Power suppry
(CP180)
(CP182)
VCC8
VCC2
QV-770
HDB