6-9 POWER SUPPLY TROUBLE SHOOTING CHART

BEFORE CHECK SW.REG. PLEASE REFER TO THE POWER SUPPLY BLOCK DIAGRAM

POWER SUPPLY OUTPUT: (A) VARIABLE OUTPUT : 90V - 160V

(DEPENDING UPON H.SYNC FREQUENCY)

(B) CONSTANT OUTPUT : 6.3V, 15V, -12V, 75V

BEAD SET

CHECK AC LINE VOLT 120V OR 220V

NG

OK

CHECK LINE

RECTIFIED & SMOOTHED VOLT

NG

ABNORMAL VARIABLE OUTPUT

MAKE SURE THAT

THE VARIABLE

OUTPUT IS NOT SHORTED

 

 

 

 

 

 

 

NO

 

 

CHECK IC401

 

CHECK F901,SW901

 

 

H-OSC SEE ITEM 1

 

 

 

 

 

YES

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

CHECK 75V LINE

 

 

 

 

 

 

 

NG

 

CHECK D919

CHECK BRIDGE

 

 

OK

 

 

RECTIFIED CIRCUIT

 

 

 

 

 

 

 

OK

CHECK START C.K.T D909,Q904,R922

OK

CHECK T901 O/P

CHECK Q911

NG

OK

OK

Q911 FAILURE

CHE (IT S

NG

OK

CHECK IC901

NG

OK

CHECK 75V,- 12V,

 

 

 

CHECK Q901

15V,

6.3V CIRCUIT

 

NG

 

 

 

 

 

 

 

IC901 FAILURE

CHECK Q901