Hi guys I'm new at this and just had a simple repair question. Recently picked up a receiver that's tripping on power supply protection after 1 second. I got the service manual and started following through. Ic 304 and 306 are both failed. These are 5vdc voltage regulators. Njm7805fa. Would you guys suggest just changing these and retesting or is there anything else in this circuit I should be having a look at first? all the transformer output voltages seem in line but the fault showed by diagnostics was ps protect 008 which means the 30v power was not detected. I'm presuming this is caused by whatever monitoring device is used not recieving it's 5vdc supply but I'm only guessing. These circuits are quite complex at first glance. Thanks in advance
Hi,
Both voltage regulators are feeding by the same rectifier KBP1030. I would check first to see if they have voltage at the input pin.
Both voltage regulators are feeding by the same rectifier KBP1030. I would check first to see if they have voltage at the input pin.
- Status
- Not open for further replies.