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3-3
ONE POINT REPAIR GUIDE
2. NO AMP POWER
If the unit doesn’t work by no ±PVDD problem, repair the set according to the following guide.
2-1. FUSE/ FET
2-1-1. Solution
Please check and replace F911, Q905~Q906 on SMPS board.
2-1-2. How to troubleshoot (Countermeasure)
1) Check if the fuse F911 is open or short-circuit.
2) Check the Drain-Source or Drain-Gate, Gate-Source Resistance of Q905~Q906 with a digital multimeter.
If it is short condition, it’s destroyed. Replace it with a new one.
(Please replace 2 FET at the same time although several FET is OK).
2-1-3. Service hint (Any picture / Remark)
< F911 >
If F911 is not short-circuit,
replace it with a same speci
fi
cations one.
< Q905~Q906 >
If Q905~Q906 is short-circuit,
replace it with a new one.
Содержание OM7550
Страница 13: ...1 12 ...
Страница 16: ...2 3 Figure 3 Step 3 Seperate Cover_Side to out direction ...
Страница 17: ...2 4 ...
Страница 21: ...2 10 ...
Страница 58: ...3 37 3 SERVO IC401 X XI XO Fig 3 2 CD 16M IC401 pin31 Fig 3 1 Crystal 16 9344 MHz X400 11 10 12 10 11 12 ...
Страница 79: ...3 75 3 76 3 MAIN VFD RMC1 P C BOARD TOP VIEW ...
Страница 80: ...3 77 3 78 4 MAIN VFD RMC1 P C BOARD BOTTOM VIEW ...
Страница 81: ...3 79 3 80 5 FRONT P C BOARD TOP VIEW 6 FRONT P C BOARD BOTTOM VIEW ...
Страница 82: ...3 81 3 82 7 TOP VOLUME_FR1 P C BOARD TOP VIEW ...
Страница 83: ...3 83 3 84 8 TOP VOLUME_FR1 P C BOARD BOTTOM VIEW ...