Printed Circuit Board - Daewoo KOT-1G0S Service Manual

PRINTED CIRCUIT BOARD

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
Voltage
Terminal
7 - 8
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.
2) Voltage Check
- KEY CHECK POINT
NO CHECK POINT
1 IC1 PIN 5
2 IC1 PIN 8
3 IC1 PIN 35 OR 36
- CHECK METHOD
NO MEASURE POINT (page 55)
1 MP1
2 MP2
NOTE :
Each measure point must be measured with GND points.
Frequency : 60Hz
LOAD NO LOAD
AC 11V AC 14.5V
+5VDC
WAVE FORM
DC +5V–0.25
DC +12V–2.0
REMARK
REMEDY
REPLACE EC1, VL1
REPLACE EC2, D13, 14
41
T : 16.67ms (60Hz)
T : 250 ns (4 MHz)
REMARK
NO LOAD
NO LOAD