Daewoo KOM-9F2CKS, Service Manual, Page: 29 / 40

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1 IC1 PIN 63, 64 5VDC
2 IC1 PIN 38
3 IC 1 PIN 33 OR PIN 34
PRINTED CIRCUIT BOARD
2. Voltage Check
- Key check point
- Check method
NOTE
1. Refer to Ciruit Diagram.
2. Secondary side voltage of the low voltage transformer changes in proportion to fluctuation of power source
oltage.
3. The allowable tolerance of the secondary voltage is within ± 5% of nominal voltage.
NOTE
Each measure point must be measured with GND points.
6-7, 7-8 DC 12V AC 25.8V
9-10 AC 2.5V AC 3.0V
Terminal Voltage LOAD NO LOAD
NO CHECK POINT REMARK
T
T : 20ms (50Hz)
5V
0V
T
T : 250 ns(4MHz)
5V
0V
1 MP1 DC 5V±0.25V Replace Q8,ZD1,EC2,R21,C2 NO LOAD
2 MP2 DC 12V±2.0V Replace D21,D22,EC3,EC4,R26,C8 NO LOAD
NO MEASURE POINT WAVE FORM REMEDY REMARK
1. CIRCUIT CHECK PROCEDURE
1. Low voltage transformer check
The low voltage transformer is located on the P.C.B.
Measuring condition: Input voltage: 240V / Frequency: 50Hz