Samsung MAX-670 Service Manual page 20

Troubleshooting
6-2 The Deck Section
6-2-1 Power Malfunction
Main PCB µ-com VDD(5V)
normal?
UIC1 pin no. 18,47,90
O
Main PCB
Does UX2(12MHz)
oscillope ?
O
Main PCB
Check µ-com vpp
pin no.48
6-4
X
Main PCB RIC4(BA7805) IN : 5V
Input voltage normal ?
Replace RIC4
Main PCB POSNS
X
voltage normal ?
(pin no. 29 ; 4.5V)
X
Replace UIC1
Check the Power PCB ;
X
RD1,RD2(IN5392)
At the base of Main PCB ;
RFS1,2 (T2A 250V)
O
X
Check the Main PCB ; CSW1
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