Daewoo KOT-170S0A, Руководство по обслуживанию

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1. CIRCUIT CHECK PROCEDURE
1) Low Voltage Transformer (DMR-210P) 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
6 - 7
8 - 10
LOAD
AC 17V
AC 2.6V
NO LOAD
AC 20V
AC 3.1V
NOTE :
Secondary side voltage of the low voltage transformer changes in proportion to fluctuation of power source
voltage.
NOTE :
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 63, 64 +5VDC
2 IC1 PIN 25 –24VDC
3 IC1 PIN 38
4 IC1 PIN 33 OR 34
5 DP1 PIN 1, 2 & PIN 32, 33 2.6 VAC (DISPLAY FILAMENT VOLTAGE)
NO MEASURE POINT (page 55) WAVE FORM REMEDY REMARK
1 MP1 DC +5V±0.25 REPLACE Q5, EC1, C8, ZD4 NO LOAD
2 MP2 DC +24V±1.0 REPLACE EC6, R28, D21~D24 NO LOAD
3 MP3 DC -24V±1.0 REPLACE ZD3, ZD6, C7, EC4 NO LOAD
T : 16.67ms (60Hz)
T : 250 ns