3-7
ONE POINT REPAIR GUIDE
AMP FET : IRF6775
< MAIN board top view >
6. NO POWER ON (STANDBY LED IS BLINKING)
It doesn’t turn on, and blinks standby LED(Red).
6-1. AMP FETs
6-1-1. Solution
Replace AMP FET on MAIN board.
6-1-2. How to troubleshoot (Countermeasure)
1) This symptom occurs, when DC protection is detected. Main reasons are like below.
- When some of AMP FETs dead.
6-1-3. Service hint (Any picture / Remark)
Notice for FET service
- In case of RF6775, Metal case, FET Drain,
has electric potential. So be careful when you
deal with it.
* You can see FET after removing heatsink.
* Notice for Service
Before repair Main Assy, you need to discharge SMPS.
After then, open the connector.
You should try to change both of +/- FET and Driver IC
as a pair.
AMP FETs
AMP FETs
(Q705~Q708, Q717, Q718)
(Q705~Q708, Q717, Q718)
Summary of Contents for OM7550
Page 13: ...1 12 ...
Page 16: ...2 3 Figure 3 Step 3 Seperate Cover_Side to out direction ...
Page 17: ...2 4 ...
Page 21: ...2 10 ...
Page 79: ...3 75 3 76 3 MAIN VFD RMC1 P C BOARD TOP VIEW ...
Page 80: ...3 77 3 78 4 MAIN VFD RMC1 P C BOARD BOTTOM VIEW ...
Page 81: ...3 79 3 80 5 FRONT P C BOARD TOP VIEW 6 FRONT P C BOARD BOTTOM VIEW ...
Page 82: ...3 81 3 82 7 TOP VOLUME_FR1 P C BOARD TOP VIEW ...
Page 83: ...3 83 3 84 8 TOP VOLUME_FR1 P C BOARD BOTTOM VIEW ...