Daewoo KOT-1G1A, Service Manual, Page: 43 / 58

42
1. CIRCUIT CHECK PROCEDURE
1) Low Voltage Transformer (DMR-161P) Check
The low voltage transformer is located on the PCB
Measuring condition : Input voltage : 120 V
Frequency : 60Hz
2) Voltage Check
- KEY CHECK POINT
- CHECK METHOD
PRINTED CIRCUIT BOARD
Voltage
Terminal
7 - 8
LOAD
AC 11V
NO LOAD
AC 14.5V
NOTE :
1. Refer to circuit Diagram (point 5)
2. Secondary side voltage of the low voltage transformer changes in proportion to fluctuation of power source
voltage.
3. The allowable tolerance of the secondary voltage is within 5% of normal voltage.
NOTE :
Each measure point must be measured with GND points.
NO CHECK POINT REMARK
1 IC1 PIN 5 +5VDC
2 IC1 PIN 8
3 IC1 PIN 35 OR 36
NO MEASURE POINT (page 55) WAVE FORM REMEDY REMARK
1 MP1 DC +5V–0.25 REPLACE EC1, VL1 NO LOAD
2 MP2 DC +12V–2.0 REPLACE EC2, D13, 14 NO LOAD
T : 16.67ms (60Hz)
T : 250 ns (4 MHz)